Hey there! I went to University of Oklahoma for undergrad, so I'm from a similar educational background, and I'll be starting my PhD at Tufts in the fall. Feel free to PM me if you have any questions about OU or about applying in general.
But so far, it seems like you're off to a great start. Don't be afraid of aiming too high, because you never know, and you sound like a great student. But of course, it's always smart to apply to a variety of programs-- in terms of both rank/prestige, as well as different types of programs. I, for one, was interested to find that a small program really seemed to suit me better.
Good luck!