Double cash would be the better choice in my opinion. That or the Chase freedom are on my list of cards to get in the future
Just for my curiosity. Why do you want to apply for anything? You have a nice arsenal of great cards, with great CLs, and extremely low balances. Your Disco card will earn you double cash back rewards during the first year and you can wrack up in categories.
As @xaximus said, it really depends on what you want from a card.
I wouldn't apply for a CC if I'm not getting anything from it. Sure, the SUB but these cards, as far as I know, do not offer AMAZING SUBs that would make me take a inquiry hit if I don't need to. If you have a reason to do it, then go ahead otherwise I would just work on the cards that you already have, try to get some credit line increases and then, maybe, apply for better cards or start working on a strategy to maxime your rewards
I don't know much about the citi DC card, but I like the citi simplicity card because they almost constantly offer balance xfers with $0 transfer fee and 10.99% rate on the transfer for 24 months - for my credit scores, that's a good rate to occasionally xfer higher-rate card balances to. You may get a better rate and SL than I did, and if you like balance xfers, I would go with the Simplicity card.
I have the Citi Double cash card, its ok but not the best. I use it for all my monthly bills like phone service, insurance, netflix ect so i can get money back for those purchases. Note that the 1 percent on purchases is only on APPROVED purchases, and only on unpaid purchases AFTER the statement is cut, so half of your purchases wont be approved, and the half that do, if you make a payment before the statement is cut, you wont earn anything on them anyway, which means if you want credit you will always have to have a reported balance. Not sure what your looking for in a card, but i dont see an AMEX on your list. I was approved for my first AMEX at around your scores, you can always go thru the preapproval first. I have a personal grudge against BOA so i wouldnt recomend thier card, and dont have experience with the Simplicity card.