I'm not opposed to power saving measures being enabled by default, but "let this app run in the background at all times" should still be a setting. Require a PIN or biometrics to toggle the setting for all I care, but not being able to turn off app killers is what turned me off several brands of phones. The defaults are good for the general population but I'm not the general population so let me turn that damn thing off. Show me a daily notification about how an app drained 40% of my battery life if you have to but don't make me root my phone again just to turn off the stupid app killer.
I run into issues with the smart watch integration app getting killed before Google Maps, even when I'm not navigating on one of my devices. No way to whitelist the integration app or set some kind of preference, it's just a lottery, probably based on guesstimated power consumption (which, for an app with a Bluetooth lock, will probably be above average) that I want to tweak.