What brand of Android phones would you guys usually go for? anything that gives smooth, AOSP, non-flashy experience?

Pixel phones are great for a clean android experience, but you have to wholeheartedly sell your soul to google.

Midrange motorola phones can also be clean and open.

I have an old refurb pixel 3 I bought to put linage OS on but it was a verizon device and has a locked bootloader. sigh so no alternate android for me.. Anyway I am using it as a daily driver with the stock pixel android package and have zero google accounts. I mainly use f-droid and adb.

Check out Aurora store as an alternative to Play Store

No Google login yet have access to all apps without the hassle of adb

I personally use F-droid + Aurora Store.

For stuff that can't use fdroid, check out obtainium, it can pull releases directly from GitHub, etc. Shizuku is also useful for background-installing apps via some of the fdroid alternative clients (and some apps like Tachiyomi can use it for extensions and other local-adb things), as is App Manager for background-installing apps via local adb.

https://github.com/ImranR98/Obtainium https://github.com/RikkaApps/Shizuku https://github.com/MuntashirAkon/AppManager