Since you have 150,000 AAdvantage miles, I am assuming that you either A. each got 1 AA 75k Citi card, or B. one of you got 2 75k AA Citi cards.

If one of you got 2, I would definitely suggest for your spouse to get 2 as well. 300,000 AAdvantage miles should be able to land 5 tickets in coach to Europe r/t.

Like the prior poster mentioned - it wouldn't hurt to get some other alliance's cards as well. You could use those for hotels or rental cards.