IMHO, grab AA card immediately while 50K bonus is available. Maybe see if you can get the AA biz card too. Check out the long thread on Citi AA apps for more info. Waiting gets you nothing except a lost chance to get a new bonus in eighteen months from date of last app.

Why don't you want to sign up for lots of cards. That's how you build up miles for free travel.

Meanwhile, think about apply for the Chase Sapphire Preferred and Chase INK.