I have been pondering the same problem for a few months now but I have a much shorter history with United. I joined the MileagePlus program on a status match/challenge 18 months ago at the Platinum level. I became 1K four months ago. I only travel for work with about 3-4 domestic trips, 3-4 TPAC trips and 1-2 TATL trips per year. My wife joins me on all the TPAC trips (usually 7-12 days) and on the TATL trips if it's more than 2 nights away from home. I do have a paid membership for the UC (paid by work). I live in a small city so have to connect through ORD.

Since I have joined the UA program, I have flown Economy + as well as paid Polaris Business + some GPUs upgrades from V, W, Q fares for the international flights + some TODs for the international flights. About 6 months ago, UA priced me out of P fares for TPAC flights out of my small city (price increases by $3500). About 2 months ago, UA priced me out of Economy fares for TATL flights out of my small city (price increases by $1200). So, I have to find alternate means to get to ORD.

Due to restrictions at work, I have to fly with an US airline but can go for a nice *A partner for the last leg of the trip if no US airline flies directly there (but that would happen only once every 5 years).

On the other side of the ledger. I have 820,000 lifetime miles with AA. I have 500,000 award miles with AA and 500,000 household Avios with BA. And now AA announced that they are coming to town in 3 months.

I don't travel enough to keep the highest level with 2 airlines. I don't know what to do. Would mid-level memberships on two airlines be better for me? Any suggestions?