I was thinking about my first booking after the switch over from Premier to Silver and it occurred to me one way United could make life easier for us 2Ps is to automate the moving of seat allocation @ T-24..

Of course it would be entirely optional. On the reservation screen you would get a series of radio buttons:
Would you like us to move you to an E+ seat if:
It is an Isle <Preference 1><Preference 2><Preference 3><No Thanks>
It is a Middle <Preference 1><Preference 2><Preference 3><No Thanks>
It is a window <Preference 1><Preference 2><Preference 3><No Thanks>

This would save the zoo at T-24..

Heck this is probably a good idea for all tiers.. like a wait-listing for seats in Y if you are not able to get into E+ at booking either because of status of full E+....