I'll probably get them all, except Arena I think. Not too keen on the idea of buying a fighting game I don't like in order to get the sequel to another bad Arc visual novel that I didn't like.
Q looks like it could be great, and an intelligent use of the Etrian engine. I like the sound of five-character battles and the newest additions brought to the Etrian engine, while (hopefully!) having the faster and more obvious character progression of Persona. One thing I'd love to see on the Vita side (but would never happen) is a collaboration with Team Muramasa, the Demon Gaze people. They've pushed user-friendliness and complex but fun and breakable systems to their current zenith in dungeon RPGs and it'd be great to see them work on something with a bit more weight behind it in terms of visual and audio design.
I wasn't too sure about the dancing one at first, but if it's by the people who did Project Diva F and has as many remixes and collaborations as they're suggesting it could be great. I still think Diva is worth it as a music game alone even if Vocaloid music is very hit or miss for me, so the things on the periphery don't matter too much. Good to hear Kuma's voice is less fucked-up than it was in Persona 4 Golden too - I was worried for the actor.
As for P5 itself, stuff like that is the reason why I've just bought a replacement Japanese PS3. I don't want to take a chance by keeping on with my old one.