This post touches on this issue: Improve back button navigation
@mrm mentions in that post that the change was implemented in 1.0 Alpha-6, but I definitely don’t have an up arrow, nor does the “back arrow” behave as an “up one level” function.
Hopefully Matthew can chime in and clarify what was implemented in Alpha-6!
I’m sure he will reply with comments on your other points, but in the mean time, welcome!!