i've been using and loving e/OS for 2 years, and I begruggingly keep a google account for GMaps and the store. I have focused on using FOSS apps, and they've been more usable than ever.
When borrowing some other phones, I feel overwhelmed by adds, nudging, restrictive and invasive designs, and sight in relief when coming back to my own phone. It's liberating.
I'm worried about the change in android third party apps policy, and I wonder how Murena will navigate this issue if f-droid disapears. Maybe your app store is the solution you're planning?
Do keep up the great work, I'll be relying on your company for years to come.