To be clear, I dropped this game today after about nine hours of playtime, mostly because I wasn't getting any joy out of it. That's not to say the story wasn't interesting, but...
Anyway, Soushin no Ars Magna is the most recent release from Ninetail, the rpg-focused sister brand of Dual Tail, the makers of the Venus Blood series... and it shows.
This game reuses a modified version of the gameplay from Venus Blood Brave, which was a more dungeon-exploration oriented game than previous entries, which tended to split between conquest strategy and dungeon defense or invasion. To be blunt, this was probably a poor choice for a game where alchemy plays such an integral part.
The dungeon exploration in the game is focused on you moving your party down specified paths one point at a time, hitting traps, enemies, treasure, or materials based on the point. This isn't necessarily an awful idea... except that for purposes of gathering materials for alchemy, it makes things unnecessarily tedious. While alchemy-based rpgs and dungeon crawlers are generally at least a little tedious at times, the relatively low returns for dungeon exploration, whether in terms of money and resources or in terms of experience and materials, makes it necessary to abuse the free dungeons... and since you can't just get what you want then leave immediately and the materials aren't always the same, this can be frustrating. This also means that there is no real sense of exploration, which is one of the attractions of a dungeon explorer game in the first place.
Story-wise, the game definitely has possibilities... but the sheer amount of grinding it takes just to strengthen your party through level gaining, finding crests, and alchemy makes it feel like you do a lot for relatively little reward. Considering that I'm comparing this to Venus Blood games at their worst, that should tell you a lot.
My impression of this game is a half-hearted attempt to reuse a more polished version of a previous system to make a few extra bucks. While the story has possibilities, the game balance is iffy at best, and the lack of better customization items speaks of laziness on the part of the makers.