Am I doing enough extra cirricular activities in high school?

I am a junior now and my grades im not worrying about because im doing fine but im only doing 2 sports this year baseball and basketball. Is it fine if I just relax, work out, and study until my winter sport starts or should i find something to do? Is two sports enough or does it look good or should i always be doing something. Also out of curiousity what kind of colleges can i get into if you look over my high school career? Freshmen year i did 1 sport football and thats it and got B's and C's for grades. Worked in the summer. Soph year I did basketball and track and got A's B's and few C's and worked over the summer. Now my junior year lets just say I get A's and B's and play baseball and basketball and work over the summer and get average SAT score like 1600 or so and I show that im a well rounded kid that plays guitar, snowboards ect... can i actually get into some decent colleges for good ones like can i get into OSU, or um, uga, and purdue can i actually get into those schools with my record? Would be not doing a sport or anything in the fall really hurt me and are my grades good enough?