Hey, completely new here. Got a question about credit cards as I only like to do one at a time since I worry about my credit (it's pretty good now, but I hear that too many applications screws it).

What card should I get next? I've already done AA-Citi card and United's Chase Visa...im at about 48k miles on AA and around 35k on United, maybe 4 points on Southwest, negligible on other airlines.

I've been lurking for a couple days and people seem to like British Airways current offer? How about Delta or Southwest?