Speaking as an Android user, the usefulness of the eco-system is undeniable and leaving that is too much friction for most, even for those who do care about privacy.

I think in addition to the focus on hardware, one approach should be to provide the tools to the users for more control. Provide a rooted phone by default. Add tools that let me see what my phone is doing behind the scenes. Give me option to turn-off some of the things I don't like (e.g. an app is sending analytics to some domain, let me turn that part off without turning off the whole app in a relatively simple way). Help with planned obsolence by providing updates etc and so on.

Basically give back some control of jail/castle to the users without asking them to leave it completely.

Edit: one more thing, please add NFC. Going back to carrying boatload of cards again is not an option.