Ask HN: Are there any viable Android phones for a power user to buy nowadays?

i have a pixel 4, and it looks like i might be stuck with this phone forever if things keep going in the same direction (hopefully they don't). the pixel 4 isn't bad, but even on this i don't have the level of customization that i had back in the day with cyanogenmod etc. on my note 3 or epic 4g touch.

here are some requirements that i can think of:

    - not huge. small enough to use with 1 hand

    - able to root and install custom OS without too much difficulty/annoyance (the manufacturer doesn't actively try to stop you from modifying your own device)
    
    - able to use mint mobile

    - has a trackball (like the htc hero, that thing was fuckin awesome)

    - possibly some hardware buttons