The .5 EQM thing on CO only matters if you are forced into booking through a corporate travel agent. Otherwise just book at co.com and get the 100%. Still, transcon upgrades are harder to come by so that may push you away from CO. So will the expectation of good IRROPS handling (they seem to be getting better, but there is a large hole to climb out of) and access to seats with legroom (transcons are mostly 739s with but one useful exit row.

UA gets you everything except reasonable access to reward inventory.

B6 gets you access to legroom and a soon to be decent program for your domestic and Caribbean travel habits, but until they announce something with EI and LH their international program does you zero good. Even with it being based on spend your transcon habits will get you into the "elite" ranks there pretty quickly.

AA seems to get you everything.