My MIBOX's Wi-Fi connection has even gotten worse. It would drop out more frequently.
I installed it. Didn't notice anything special except VLC lost it's network login but that's an easy fix... and twitch now pops up network error warnings every ten minutes or so, but that might be something local.
My Android TV app won't connect any more. Casting still works, so it's not a network issue.
Most of the fixes are stated in your picture.
My remote doesn't connect after the update. It did right before, what to do? Already did the press back and home button hold until beep a few times.
The volume buttons control Netflix for me now, using a av receiver.
There's been a thread here with a ton of discussion about it already:
https://www.reddit.com/r/AndroidTV/comments/9epmm8/mi_box_mdz16ab_updated_to_2303/