I've done many wings with both the epoxy method and the CA method, they both work. I tend to use epoxy since it doesn't make all those pesky fumes.

30 minute epoxy will work, thinned epoxy will work even better. But the best is 20 minute finish cure. It's made for glassing, doesn't need thinning and it sands easier.

Yes you can let one side cure before doing the other side. Gets way too messy if you don't.

Dave