The big difference that I see, comparing UA to European short haul carriers, is that it takes UA at least 15 minutes longer to board a 737 than it does LH, EI, SK or BA a 320 - comparable planes. And longer still than FR and U2, the other airlines I fly regularly.

And this comes down to the passengers who seem to take forever fiddling around trying to put several bags each in the overhead bins. Perhaps Basic Economy will help this.