My expectations are that the airline will get me there in the cabin that I have paid for. My status usually will get me a reasonable seat location. As long as they don't muck around with my preselection I'll be happy.
Upgrades are as much a function of routing and season as the airline. Having said that AA has been very good when using the 500m coupons even at the airport with weather issues. AA were very generous to my son after a scheduling fiasco out of LEX into ORD. BA and CX have occasionally been very generous... But I try to book WT+ on BA. QF never offers anything but ODUs sometimes work if you have the (large number of ) miles in your account.
YMMV as you wander
Fred