Buffalotrvlr13

I apologize in advance if this is a newbie question, new to the whole travel world and just started focusing on getting the most out of my time away from home...

I fly out of Buffalo, NY and typically book with less than 1 months notice, all over the US except west coast, Mexico, Europe, and Asia. I have flown 73,000 miles as of today on United this year and will be over 75k after next week.

So far I will admit I have not spent TOO much time on fare classes, specific segments, etc. But have started to the last 15k or so. I travel on the companies dime, not heavily regulated but if it looks TOO out of line it will get checked so booking first directly is almost never going to be an option.

Since my travel is fairly last minute with strict dates upgrades are very important to me vs some of the other perks (as I'm sure it is for everyone else).

Have not had ANY luck so far being upgraded domestically, and was just upgraded on Taipei to Narita, but nothing rest of the way through (NArita to Ohare to Buff).

My first question is do they weigh the statuses the same or will a 85k trump a 76k? Or does the fare factors come into play prior to that?

Second is, given my home base, and frequency of overseas travel, does anyone feel that US air is a better choice for my travel?

Thanks for any and all input in advance.. ^