I own so many of these games, yet I've played so few.

First up: SMTV-Vengeance is coming out soon, middle of June. I played the OG version until about the 3rd area and put it aside. Hate to say, "bored of it" but kind of that. Yet, I will probably pick up SMTV/V here in a month and give it a whirl (especially since it's available now on PC; Hello Steam Deck).

Anyone into this series, persona or any of the various Devil spinoffs? What's the consensus here?

I think the only game in the entire series and spinoffs I've completed would be Devil Survivor Overclocked, which I just wrapped. I think I finally got the hang of combining demons and made it work pretty well. Game was fairly difficult but allowed for easy grinding to power your way through difficulty spikes, which I appreciate.