Nice changes for #1 and 2 - only did a flight in A once, and have strategically ensures my flights were in A and 3 since then.

I've done YYC flights on UA from gate 70 before, and the only drawback is the loooong walk to G if you want some duty free, as there are no mini/mobile shops like other airports have. It may not be the cheapest, but I have an arrangement with a parking attendant at an airport that exchanges Gin for a same-day parking entry ticket - worth it

As for the MLL, I can absolutely see it being swamped by UA members, but I haven't even stepped into a United Lounge (not even the brand new one) since they opened the Centurion Lounge.