Sideloading apps on iOS has gotten a lot easier. I use sideloadly. It has to connect to your computer (wirelessly) once a week but does this automatically in the background. I’m still running Apollo, the best Reddit iOS app this way.
I have YT premium through Sri Lanka for $3/mo. Sponsorblock works in safari.
ROM apps like delta are in the App Store now. I have no idea about phone gaming otherwise.
Never ran into any content filtering.
If your gf uses iOS try it out there first and see how you like it.
New iPhones release on a pretty strict schedule each September so even if you don’t want the new model best to wait for older ones to be discounted.