A Good Game in its Own Right
I'd never actually played a Shadow Hearts game before picking up Shadow Hearts: From the New World, so I can judge it on its own basis and not how it compares to its predecessors.
Shadow Hearts: From the New World is a pretty good game. The combat system is fun and can be quite challenging as it depends on how well the player can handle the judgement ring system. Everything operates on that system - from attacking, to healing, to reviving players. If you choose to double attack, hope that you hit the judgement ring and that you've not just let yourself die by being unable to heal the characters, for instance. It leaves a lot of room for strategy, although the game doesn't force you to use its systems either: I got through it without ever using a combo attack and with little or no use of stellar magic beyond healing and support spells. The game can be punishing at times if you take your time in battles and end up running out of sanity points, but this is only really an issue at the beginning of the game.
The story and the characters are somewhat less polished. The story meanders for quite a while before the intentions of the villains are really established, although they are quite interesting characters in their own right. In some respects, the villains are more interesting and fleshed out than the main characters. While the player can embark on sidequests to gain new character abilities and learn more about their respective characters, it feels a little tacked on. Characters such as Johnny and Shania have their pasts tied into the main plot in some way, but the others just seem to be there on occasion. That said, the game does tend to remember certain characters for particular exchanges, which is good.
Why such a high score if such points are flawed? Because Shadow Hearts: From the New World is fun. The combat system makes up quite a bit for the areas that are more unpolished, and the encounter rate is low enough to avoid annoying the playing (although it can be increased). The game, while having a fairly serious plot, doesn't take itself at all seriously, leading to some genuinely funny moment. I'd rather play a game that has some flaws that I enjoy than a technically perfect one that's boring, so it's four stars from me.