Some thoughts I have got after reading flyertalk's forums a little while...

I wanna build more miles on specifically AAdvantage and United Mileage Plus/OnePass, because of the stupid airport location I have, PHL, which makes it much tougher for getting sick deals, unless, I don't mind going for commute from PHL to NYC via car, NJ Transit, or Amtrak. I don't like United's service, but the fact that cheap tickets are always found for PHL take-offs via United.

My questions are:

1. If I wanna build more mileages, do you think I should try to just stick with AAdvantage or United every time I fly? I know AA doesn't allow matching status, while United doesn't either, but CO does!

2. Do you think it's actually nice for me to just build my own itinerary instead of trusting the United/AA's websites for suggested connections and stuff? Let's say, I wanna do AA from PHL to SFO, I know sometimes BOS to SFO offers cheap tix, so I can get the tix from PHL to BOS via USAirways, which is cheap, get the miles on United/CO, then put the rest of BOS-SFO on AA? I notice that AA only does PHL - ORD, or PHL to DFW, while United does not just PHL - SFO non-stop, but also to different multiple locations.

PS: I really like AA and CO more, not so much for United...

3. Worst life ever is I am a lover of Marriott and I like getting the points instead of really transferring the points to miles to United/CO(I know AA cannot do it). I never go for Hilton, Hyatt. Maybe some times in Holiday Inn....

4. Any recommendations on the credit cards for AA or United/CO miles? I am pondering which one I should get, but I have to take into account that the membership fees are pretty high for some of the reward mileage cards too. Any most economical CCs that not only build my credit, but it also helps build up the miles fast while it doesn't require membership fees say more than $50 a year?

Any idea will be deeply appreciative.