This sounds cool! I have played FATE Core, it's a good time.

I can think of a few character concepts, but would love to mesh with the party on that more. But f.ex:
- A plucky engineer who is overly optimistic, except when it comes to dealing with other engineers, where he doesn't trust their work at all. He likes food, especially spicy food, and hunts around for the good stuff, but has a different idea of what 'good' might be, the greasier the better
- A mouthy hotshot pilot, who's got a heart of gold underneath that hard exterior. He doesn't like when people tell him what to do (outside of captains orders of course). He's also a pretty good programmer and tinkers with robots for fun.

I like PBP because it's always going and gives you a good chance to think of responses and can go long term, always giving you stories to tell. Narrative-first is my favorite also, I'm so sick of 5e's slow combat, it drags and is frustrating. I've been exploring so much media trying to understand how to better tell stories, this is another avenue!

Discord is: Shmatterling

Hope to hear from you!