Ah, another privacy-oriented phone project. As if the Pine-, Libre-, Jolla-, Neo900- etc. etc. endeavours weren't successful enough.
I was wondering - what is the status of those projects? And because they are (mostly?) open source, why not start with one of them?
Jolla added libhybris to make it easy to use Android hardware adaptations - which at that time was needed to get a phone out (ste, which the first Jolla phone was supposed to be based on, decided to get out of the phone chip business during the prototyping phase, and that was the last vendor offering proper Linux drivers). I never was much of a fan of that as you just pull in way too much uncontrollable crap - unfortunately it works good enough that a lot of other projects then also jumped on that, instead of reviving a focus of doing proper Linux drivers (something I was worried might happen when the libhybris development started).