I've been meaning to do this for a longer while now, but various circumstances always prevented me from making it.
Before we start, let me make this clear. I dislike value-based rating systems, where numbers are supposed to be an estimate on how "good" something is, or how much quality there is to it. In my opinion, those systems are all fair and square but don't really work the way we'd like them to, not to mention a simple number is vague as hell and doesn't really provide anything except a scale between "good", "bad" and "mediocre" in-between. Why is that? Because vns don't work that way, sadly. You can't really rate a visual novel in the same exact manner as a standard Hollywood movie, plastering a number on top of it; it's because vns are insanely diversified works with many unique sub-genres, built with particular audiences in mind. It's a world, where one fan's treasures are another fan's trash, often within the same genre trees. The same can be said about almost every other work medium belonging to japanese pop culture. Discarding this tiny nuance might actually have a pretty detrimental result in terms of ratings, that are either too vague, unfair or way too hedonist, without actually trying to get the gist of what the game actually is and to whom it is addressed. I'd rather want to think of actual ratings as something that helps in deciding how much a game is in line with one's personal interests and how high that goes. Different groups of players have different needs, therefore it's probably easier to explain the whole thing in form of a diagram:
Don't think of it as "things consuming things", but more as "things supporting other things". Moege aren't particularly worse than high-rated vns, they simply have a completely different target audience, with completely different set of tastes and demands. Obviously, certain genres are more common - because there's a much higher demand for those, but at the same time it means lowering standards to match tastes of a far wider audience, which uniquely leads to genre blandness (this happened to moege and majority of charage already). The games higher on the list in terms of complexity are more streamlined and niche, requiring more refined tastes and greater knowledge in a variety of topics, which leads to them being far less approachable by majority of players. This by default leads to subsequent categorization and further alienation which is one of the major reasons why it's so hard to get into those games and communities that surround them.
Those tiers are permanent and games belonging to them remain forever bound to their respective positions within the chain. It can't be changed, nor affected in any way, as accessibility by ease of understanding is the sole factor that decides about their fate. This also lead me to believe, that a proper rating system should actually take this into consideration. As much as you play a high-tier chuunige for it's cool story and characters, you play a simple charage not for the plot, but for character interactions and protagonist finally connecting with one of the heroines; you want to see where their relationships will lead to and it's the only actual thing you will care about. It's not really possible to compare both through the same exact value-based rating system.
Obviously, we could argue about this forever, so without further ado - I present my new rating system, I'll be using onwards for my vn reviews.
Basic ratings go as follows:
Awful - When things get so bad, you might as well ask yourself what kind of wrong have you committed to end up with such game in your hands. Somehow, you ended up picking it along the way - maybe because it had a cute maid on the cover or a synopsis, which looked particularly interesting; who knows. The point is - the more you play, the less impressed you are and by the time you reach the end, you might be banging your head against the desk in utter disappointment and resentment you ever got yourself into vns. Looks can be deceiving, after all. Avoid whenever possible, since there's probably a thousand things more worth wasting your time on, than crap in p(r)etty disguise.
Hopefully, I won't ever stumble upon a game, that will prompt me to give it a lower score.
Imperfect - Games that strive to be good, but fail somewhere along the way - in one or more aspects. Typically a result of many problems piling up on the dev side of things, including lack of proper knowledge, skills, financial aspects, neglect, and/or faggotry. Those titles might (and prolly will) be enjoyable, but often most, the amount of issues outweighs positive aspects, successfully lowering the enjoyment factor to a large degree. They range from being mildly obnoxious in their issues to outright annoying and might be even riddled with bugs. Needless to say, they should be played in moderation to avoid salt overdose and in most cases, only the most devoted fans are arguably able to look past their flaws. For every imperfect game, you will find at least few similar titles that don't suck as badly.
Mediocre - Games considered a widely accepted quality norm, stuck at their designated level. Mediocre titles tend to be far simpler in nature and typically offer fair value from a consumer standpoint, but lack in soul and technical aspects, making them cheap in comparison with anything above their tier. They tend to be mostly forgettable and don't leave a long-lasting impression (exceptions happen), but remain enjoyable while they last, giving you something to do for a bunch of cozy afternoons. In overall, they tend to leave players with hunger for more and unfulfilled dreams. Expect whatever being mass-produced at current moment to fall under this group, including majority of moege. At times, I tend to leave them with a tiny +, to indicate devs at least tried.
Impressive - A game, which elevates itself above norm and skilfully uses tropes, settings and standards along with various medium-related mechanics to create memorable experiences. Those are typically good games by default, albeit not devoid of flaws, often times being a part of their very nature. They still tend to be far from perfect, but you'll love them regardless of those tiny mistakes and bumps, which remain an indicator of hand-crafted approach. Titles as such aren't uncommon, but more than often - they will leave you thirsty for more and that thirst is something, they aren't really capable to quench; after many of those, you will most probably want to delve deeper. They will purposefully tingle your ego, but don't expect them to give you clear answers, nor solutions to problems they create. They are more often about the voyage itself - asking questions and leaving their readers in a state of bewilderment - rather than the end result. Nonetheless, they are almost always a truly enjoyable ride till the very end. This group tends to attract simpler story-heavy games, as well as more ambitious charage titles.
Outstanding - Very few games reach this sort of artistry, that could be only matched with writers' attention to detail and cleverness in which they build their settings and play with commonly found tropes, much to everyone's surprise and delight of their more hardcore fanbase. In those, the definition of up and down doesn't really exist and any sort of distinctions between what's considered widely accepted moral norms blur to the point of being almost indistinguishable. They rarely give a damn about normalfaggotry conceptions of the perceived genres. Such games will often have great heroes and even greater antagonists - actual people made of flesh and blood, driven by most primal human desires and emotions that will defy physics, bend time and space, obliterate entire armies and cause nations to fall. Such characters often find themselves fighting no less with their enemies, as much as themselves - their flaws, imperfections, inner demons hidden somewhere between the folds of their souls and enjoying to peek outside at times. In those tales, people will die and things get destroyed, with certain fates becoming far worse than a visit to the nearest afterworld. Don't expect your favourite characters getting selective treatment; in realm of outstanding stories, characters considered to be "redeeming" or "favourable" often go through even bigger hell than defeated antagonists - at most if they win - with worst possible cases including moral event horizon induced insanity, gruesome deaths or eternal suffering (preferably all in a never-ending cycle). Those stories will make you laugh, they will make you cry, they are frequently emotionally draining - and boy oh boy - entertaining as hell, provided you're capable to grasp concepts behind their inner workings.
Considered a desired habitable zone by many aspiring and skilful writers, simply because it allows badassery to exist without hurting immersion in the process.
Brilliant - Games that ultimately defy laws and conventions of genres they belong to, written by literate geniuses, capable to mould words into whatever the hell they want. Plot no longer functions like in normal space and characters are akin to visitors on a vast plane of reader's subconsciousness. Those games are typically considered difficult to grasp for most people and with a good reason, because you're expected to deal with creators themselves and whatever personal issues, grudges, hate and passions they throw at you, while you're trying to make sense of everything. They are extremely rare and as such, prone to complete subjectiveness, becoming battlefronts for fan-based warfare. They always attain a cult following and grow endless forests of epileptic trees, which serve as fuel for discussions, that will go on for years - AND YEARS, if not decades after release.
Masterpiece - This, my ladies and gentlemen - is what any fan could consider a holy grail of eroge... if one would only exist. I doubt I'll ever come across a visual novel as good, to be able to freely - and without doubts - give it such a high rating. It didn't happen yet, perhaps I'm yet to read them, who knows. Most of the really good games I know fall somewhere between outstanding and brilliant, to give an example. This rating is more of a gimmick to keep myself at bay there are no perfect games.
In addition, I use the following special tags as well:
Highly recommended - Games I consider being capable of showing "how things should be done", both in terms of writing as well as genre standards and rules they operate under. Such works, are - more or less - exemplary and at the same time - provide both content and enjoyment in a way, that's easy to grasp even for novices and people unaccustomed with their tropes or elements.
Guilty pleasure - You DON'T question why certain games get this tag. Period.
This is something I typically reserve for titles, that might not really be the best or most worthy of attention or general context (I could quite possibly not play them under most circumstances), but definitely deliver elsewhere. Where the former doesn't apply, they simply have things I have a strong and particular fixation about and approach them in such an excellent way - including fetishes I can't really live without anymore - I'm able to forgive those games any other flaws. I don't really play them because of their depth or plot, I play them for my personal enjoyment on a very carnal level and you might find them of equal interest.
Wicked - A game that breaks any contrived norms or standards and does it in a fashion, that's definitely worth praising. I use this tag specifically for games that are a cherry on the top amongst the more morally ambiguous titles, often scaling between "cute", "awful" and outright "disgusting". Those games usually throw players into a vortex of extreme emotions, crushing their hopes and uplifting them seconds after, only to cast them into despair once again; The sort of games, that leave you both with sense of a profound disapproval and an almighty grin on your face. TL&DR Games that are literally a blast to plough through, provided you are both physically and emotionally strong enough (lol).
For those of you, who ever wondered how do I rate the games I play, or what's my perception of vns in general this hopefully clears things up, even if a little bit.