Google Pixel alternatives?

I'm thinking of getting a second phone to ease off iOS. It has been good for productivity stuff but the closed off nature of the device keeps disrupting my plans. Everything is either expensive or ad ridden. (Except floccus, floccus is awesome)

So far I have read about graphene OS and am quite interested. I really despise google though. Any chance to use another device and put some linux flavor on it? I was playing with the idea of a pinephone but it seems to be nowhere near daily drivable, fairphone is starting at 580 €, volla phone (german) 450 €...

Some people said xiaomi should be rootable. But the amount of different phones is huge. The price range is awesome though. I was thinking sub 300 €/$ would be awesome so tinkering doesnt hurt me financially.

Disclaimer: I dont want to go full hermit mode with no sim and a faraday bag. I respect the opinion but thats not what I'm trying to do. I want to write some small apps for my phone and use it as a computer if needed. Calling, matrix and browser should work flawlessly.

Any ideas or suggestions? :)