History-

2nd week of May to Mid May 2011 - applied and approved for British Airways (100k) , Continental (50k) and 2 Citi (visa and amex)

late June 2011 - applied and approved for Chase Sapphire Preferred.

I would like to have the Citi Business (75k), SPG AMEX (30k) and possibly the Alaska Air(40k).

Should I wait a bit? Is the best strategy to apply for two at once or one at a time? Which is the best one to apply for now or later (how much later)? I only had ONE AMEX card but that was in the late 80s and has been cancelled for at least 10 years. I don't have a hotel card at all.

Thanks in advance