It depends how many cards you have and what your CLs total and what your balances total, and how closing the cards would affect those numbers. If closing those cards wouldn't affect the numbers and if you have several other cards, I don't think closing these cards would numerically affect your score much. The other question is if closing accounts too early might set off "churner" automated alarms, even though these particular cards aren't ones anybody would churn. I doubt it, but that is something I'd think about, if in your place.
If the Platinum is unsecured, you can change it for the QuickSilver with no annual fee after about five or six months. And if the QuickSilver is the version without an annual fee, personally, I'd keep it for random spend when I don't have a category covered with another card, or just for CL ballast. If it's the QuickSilver version with an annual fee, I would suggest closing it before the next annual fee is due. That said, if you just don't like Cap 1 or something, closing won't kill you. Good luck!
