The main thing I come back to looking back on P5 is that it's a real ass sequel in a way we're not used to seeing anymore. With diminishing graphical returns, shrinking windows between sequels, etc, a lot of the times a sequel feels less like taking a franchise to the next level and more like a fresh paint of coat on the thing you've been doing for a while.
On a presentation level, at the very least, P5 is a huge evolution. Now I'm not saying that it's the best looking game technically but frankly, Persona 4 and 3 were kinda... busted. They were busted looking. They didn't really look good for PS2 games, or even PS2 games from Atlus (compare them to Nocturne, for instance). That didn't hold them back because of how interesting and charming they were otherwise, but...
This is the first HD Persona game, and boy howdy does it show. I don't know if, on some math nerd level you could say it looks "SUBJECTIVELY BETTER" than something like say, FF13 or Nights of Azure or whatever, but between the the overall art style, the animations, the UI... it's definitely a lot more fun to look at.
I enjoyed the gameplay changes/additions too, but they feel a bit more in line with what you'd expect from a sequel. Good stuff, but not quite as remarkable as going from tiny big-headed puppet people putzing around diorama-esque environments to big ass cel shaded style dynamos strutting around cinematic camera angle city.
And regarding the story... I'll just say that an opportunity was missed by it not having simultaneous English release. Will be curious to see what people think of it in February, depending on what happens in the US in November