Welcome to the forum! And congrats on establishing a credit profile at such a young age. You currently have some good cards in your arsenal. As far as what to apply for. I would hold off until the scores climb up a little bit more towards 640 and higher. Reason being is that you just don't want to apply to get a card. You also want to qualify for the best terms and SUB. And if your goal is to establish strong relationships with a specific lender of choice, it's best to show them first that you are able to manage credit. Your scores alone are just one factor in the approval process. Your age, income, and other factors would also come into play, the more history you put into your existing accounts, (e.g. On time payments, usage history, reduced inquiries) the better odds of getting approved for a prime credit card.
