Thanks for sharing your experience, I'm glad to hear that mobile linux is practical for some people. What do you do for GPS? And in day-to-day use, doesn't WayDroid drain the battery?
When it comes to Waydroid, I boot it up very rarely and usually just to do something specific and stop the container afterwards, so it's not a concern. But if you wanted to keep it loaded for fast access (booting it up takes about half a minute) you can either freeze the container or just suspend the entire phone and it shouldn't influence anything other than keeping RAM occupied.