SF Nino or SP Camilla for green flier?

Spring Camilla is good defensively as a colorless counter with Raventome and TA

SF!Nino is obviously offensive, and yours has perfect IVs for it. And Nino works perfectly fine with Giga Exc imo

I'd vote for Camilla. You already have 2 bladetome units on your team, so having a bulky unit that can take a hit can be beneficial.

Of course you can always just have 3 nukers so you can just eviscerate everything.

I'm going to be honest; if I were you, I'd do neither of these. A team with three mage fliers is REALLY shady because you essentially have no real tanking power (which is usually good to have to at least some extent, even on offense-based teams). Additionally, you don't have any strong source of physical damage for in case there's some sort of powerful Res-based wall. Archers like Innes become deadly due to their high res, defense targeting, and effectiveness versus fliers. Sure Blade tomes can usually break anything but it's usually good to be more balanced. I highly recommend Cherche.

If you're dead-set on having a three-mage team, then definitely go for Spring Camilla. It gives you an option for against these archers, and even if she won't be able to do much damage in return, she can at least tank them. Close Counter is solid on her, I've heard.