I haven't touched Akira's route yet at the time of writing, so my feelings may change with time, but man this game is good. It's by no means perfect (we'll get to that), and I do wish it hadn't completely done away with the post-apocalyptic setting of the previous two games, but if what you're after is just straight dungeon crawling without any filler*, then this is the game for you. There are tons of quality of life changes made from SMT2 that make the game a lot better to play, the soundtrack just takes all the compositions that worked and adds to them, and in general this feels like the devs taking what they learnt and building upon it.

All that being said, this game has one absolutely MASSIVE flaw, which is the Domain of Sloth. This dungeon is one of the absolute worst pieces of game design I've ever seen, and almost singlehandedly killed my motivation for the game. When I give this game 4 stars, I am choosing to mostly overlook this dungeon, because it's so bad that I don't even feel like it's fair to count it, especially when the rest of the game is as good as it is. If you haven't played the game before you might be thinking "oh it can't possibly be that bad", but trust me it is. The Domain of Sloth forces you to grind, but not just in the sense of needing to level up more to overcome a tough difficulty spike, no this dungeon literally locks progression behind walking back and forth for several hours. In any game this would be bad enough on its own, but one of the core mechanics of this game is that there are multiple distinct routes with unique content, and 3/4 of them visit the Domain of Sloth. So this dungeon isn't just badly designed, it goes against the design of the rest of the game.

Overall though, this game really is quite good. The Domain of Sloth may kill it for some, but I do feel like beyond that there's still a great game to be had.