Machina4 Mentions of Mistique and Misty bring to mind... how would Zero's power affect someone transformed? Would it bring them back to their original form or just stop them being able to transform again?
I remember rogue found out Mistique tricked her into hating the X-Men by touching her, but I think she was already in her original form? As well as when that kid that... has Zero's power but as a laser hit her...
About having guys... they are already there, just only Xavier is actually shown. Hank is the one dealing with the lab and microtransactions, Wolverine and Cyclops are mentioned as training you in the Danger Room, and Nightcrawler was already mentioned about freaking you out after a conversation about what would happen if you cancel his power mid-jump.
But only like that, no actual talk or even appearing as a background mob for them.
Anyway, coupled with your suggestion of knowledges, this could kinda become a new game on its own, save for the art. If you would ever want to try, you got my approval (for whatever much it may matter)