If you want to go for privacy, specifically through using a "vanilla" system (as close to the base Android as possible, at most with some FOSS apps), you'll lose some stuff, like most banking apps, since those usually require Google Services.
Also though the main app source for Android is Google's Play Store, you can find some useful stuff on places like F-Droid (for utilities from my experience) and Itchio (for games in my experience). There's some more places but they're usually much smaller or not as easy to sort by Android.
I have a bias that favours tinkering systems, so if you'd be curious about something different or if I use some jargon you don't know, please do point out.