P2 needs an overhaul. Yes, it's story and characters have their strengths, and the "rumor" system was novel for its time, but absolutely everything else about it would not fly among at all to engage with mass consumers.
The combat is both sluggish and dense in the worst ways. Very high encounter rates and long protracted fights, it's just droll. It's tactical grid-based system is neither interesting or engaging and there is a reason most players recommend persona guides to effectively bypass the poor pacing of it all. The tarot system and demon conversation system is antiquated, irrational, and focuses on luck with trial and error sussing out keyhole responses over thoughtful engagement. These aren't real conversations to win over demons but rather dumb and repetitive memory games to suss out which coded response works among dozen of identical word choices. It expands on P1 by merely increasing the number of variables to choose from, which just bloats the design methodology in a poor manner. Pick the wrong combo of words and sorry! Try again next time!! It's vague and illogical in practice to woo over demons. Again, people recommend guides for a reason to smooth out the actual act of playing. It's the worst playing Persona of all I'd argue.
Not sure if an overhaul that reworks everything into the press-turn system with a normal "fusion" system would be the right call as it saps the identity of P2, but I'm not sure how you even rebuild the old game design without going bold and new entirely. Modern fans may reject how distant these game function from how P3-5 play(social links, time mgmt, press-turn), but it will take real risk and imagination to transform the bones of these games into something modern audiences flock to.
