AA, CO/UA are the two programs I have accumulated miles. I also have a RT in Southwest. I'll stick with those three and get some hotel points for now.

I use AA, CO/UA for international and Southwest for domestic flights. I travel twice a year, one domestic and one international where I go to different parts of the world and wander around for a couple months in the winter.

I usually fly coach so I can keep my miles for other trips but might go first class on my next trip if I can keep enough miles for one other international trip. I'm thinking I can get some nice CC bonuses in a couple years so why not.

Can you also book hotel rooms in someone else's name?