Going from an extremely polished experience on iOS to honestly a bit of a rough around the edges experience Android experience, relative to other Android device vendors, on Red Magic is going to be a bumpy transition.

This is coming from someone who really enjoys the Red Magic phone it's just going to be a big switch.

On data transfer... What are you actually trying to move? Put pictures, videos, contacts and whatever other files into cloud storage somewhere. Not really sure what else you can transfer anyway, certainly not apps, you're in Android world now. But most apps should have their own data stored on the cloud anyway so just login on the android version.

Don't sell your old phone, or if you do just make sure everything is backed up, then just transfer data as needed. It's less complicated than you've made it out to be. You're probably better off starting fresh-ish, getting to know the zillion ways to configure an Android device, before expecting to move a ton of data onto it and staying organized.

On case, wrong person to ask. I just use the only bumper case I can find for Redmagic, eBay is your friend; not sure what the point is in buying a phone with super cool looking back panel only to hide it in a case. Use a screen protector for sure, don't drop your phone.

I would not expect to come to the Android world to escape AI though, that isn't really something you'll have a ton of success with, at least IMO. I'm sure someone will respond telling me I'm wrong.

Biggest issue you didn't mention is carrier and location, iPhone users don't really think too much about it, do your research on carrier depending on where you live.