Caramel Box is one of my favorite companies. I'll say that right off the bat. They have one of the best writing/producing teams in the business, and it tends to show. Not only that, but their VNs tend to run the gamut, all the way from nakige to chuunige. While artist-freaks will sometimes nitpick on the details of their CGs, their artistic style is unique in VNs, retaining some older techniques and mixing it with new. In addition, their musical choices are similarly odd, frequently utilizing tunes that you normally wouldn't expect to create powerful emotional effects and shape the atmosphere of certain scenes.
Another issue is that there is that they have a tendency to disregard many of the cliches of the industry. In most of their VNs, the classic heroine archetypes are either nonexistent or used in a different fashion than is common to other VNs, and I've yet to read one of their VNs that fell into the trap that is the 'non-entity protagonist' that so many other companies allow themselves to be caught in.
To give you an idea of what I mean by the wide variations in this company's choice of genres...
Toppara- Nakige/charage with a strong element of catharsis and self-healing that led me to add it to my 'Chicken Soup for the Soul' list. It also has only one human heroine... and a total of nine heroines, lol.
Shuumatsu Shoujo Gensou Alicematic- A fantasy chuunige, with a direct Cthulhu Mythos theme to it. The addition of serious, well-researched sword techniques combined with elements of the mythos drawn straight from Lovecraft's own works was impressive, even to my relatively inexperienced brain at the time I played it.
Semiramis no Tenbin- A social commentary combined with a deep personal drama and a quite deliberate denial of moral absolutism in regards to matters of law and human relations, all wrapped up in the interactions between a near-sociopathic heroine and the inhabitants of the protagonist's own surroundings.
Otoboku (series)- The original cross-dresser protagonist VN and its kamige sequel. The combination of Taisei-era girl's school otome storytelling with modern charage/nakige techniques has become something of a signature for the genre in general, though most don't manage to recreate the same atmosphere.
Aekanaru Sekai no Owari ni- A somewhat average-quality hard science fiction based in a dystopian future of underground arcologies.
Boku no Te no Naka no Rakuen- A classic fantasy-style story in a fictional world, with a typically amnesiac protagonist with special powers... that somehow manages to be enjoyable anyway.
Meguri Megureba Meguru Toki- Supernatural ghost story, with two distinct sides, each with two heroines... the supernatural and the non-supernatural. The contrast between the two is one of the more fascinating aspects of this VN and it is the reason why I consider this VN a potential recommendation to people who like to read things for their 'atmosphere'.
Komorebi no Nostalgica- This isn't technically by Caramel Box, but it was both (partially) funded by it and written and drawn by their main team, so it might as well have been. It is a hard science fiction story based in a post-WWIII world where almost everything before the war was lost - culturally, and its society has changed radically due to the coexistence with the sentient AIs known as Metosera. It begins with the awakening of an old-model android named Cinema, who provides a window on the world before the war as well as showing an alternative to the Metosera's own AI evolution. This VN touches on many of the negatives and positives brought up in science fiction in regards to AI technology in a thoughtful and deep fashion while also providing a deeply emotional story and a wonderfully well-developed cast of unique characters.
Edit: You can see why I consider this to be a somewhat oddball company, can't you? This company generally produces high-quality VNs in such a wide variety of genres and messages/themes that it is impossible to pin down anything other than their style, which is also unique. I honestly haven't encountered a team or company that does things the way this one does, and for that reason, I think most people reading Japanese VNS should at least try some of their works.
Edit2: For those who haven't read some of my other comments on VN companies in general, I should probably explain something about the average VN company. Most companies retain one or two teams, usually specializing in the same type of VN, with members switching out at irregular intervals. This is a lot of the reason for the massive drops and rises in quality you see in a lot of VN companies. A company with a single team whose members are pretty much the same as when the company was started is almost unheard of... and that that team has produced such a large variance in the nature of its VNs, whether it was genre-wise or in terms of theme, is also extremely unusual.
As an extreme example, Whirlpool produce charage with story... always. There are variances in the balance of moe, character, development, and story, but the general nature of their VNs doesn't really change. The same can be said for Nitroplus, which produces three types of VNs from three different teams... dark fantasy chuunige (the Muramasa and Jingai Makyou team), psychedelic fantasy (the Sumaga Team), and the Science series team, which produces VNs that are... a bit 'different'. Nonetheless, all these VNs still produce a basic 'area' of the VN industry that the company as a whole specializes in. Yet another would be Navel, which specializes in generic charage, while occasionally experimenting with more unusual projects such as Tsuriotsu.
Even if a company covers multiple 'areas', those areas are generally very narrow, such as Front Wing and its split between nukige and story-focused VNs such as Grisaia and Hatsuru (they might not seem to have commonality, but the protagonist of Hatsuru has a lot of the same self-hating qualities that Yuuji had).