I bank with AA. Basically I tend not to use my miles "lightly", eg, domestic trips or even simple international rt's. I like to keep them for One World awards, like visiting (from ORD) several of SFO, NRT, HKG, BKK, SIN, DEL, NBO, IST, LHR, NYC in business class: friends or family in many of those places. ^

For simple round-trips, I prefer to buy my own ticket, so I can earn more miles for the trip, but I would buy award tickets for family members, depending on the situation.

Please note that at least with AA your status does not depend on how many miles your account has at the moment. In depends on how many paid miles you flew during the past year or how many lifetime miles you have earned form all sources including flying, credit cards, gifts, CS bonuses resulting from complaints, etc, whether they are sitting in the account or have been spent.