Maybe it would be possible to check unlock status and drop down to home screen if authenticated?
Regarding your second point, Poweramp seems to override showing most recently used app when unlocking, which I regard as normal behaviour. i.e. When I have the Poweramp lock screen UI enabled, it will always open Poweramp whenever I unlock.
To clarify - I'm essentially requesting a change of behaviour when activating the screen and not unlocking (pressing the lock button, or using knockON) vs unlocking (using facial recognition, fingerprint scanner, etc.)