DO NOT TAKE TOO MANY COURSES!!!
This is from experience. I recently graduated with a degree in Biochem and a minor in Russian Studies. I also was interested in a bunch of other stuff, so I decided to just take a lot of other courses....BIG MISTAKE!!! My school was on the quarter system, so three courses is a full load and four is heavy, depending on how many units each class is worth. I regularly petitioned to take five or six courses a quarter, plus I took online courses on the side at a community college. MY GRADES SUFFERED. The one time I took three classes, I got straight A's. The three times I took 6 classes, I averaged ~3.3. There is a BIG difference. I should have learned, but I never stopped to think about it and learn from it.
It sounds to me like you have similar interests in taking course for fun when you might jip yourself of time to study for your more difficult courses. While this is alright if you have time to dedicate to each course, MAKE SURE YOU HAVE TIME.
Also, it depends on how much time you devote to EC's. I played sports and worked in a lab, and in between seasons I volunteered at a hospice. Do these EC's sound familiar to you? If they do, DON'T overdo it on your courses.
Hope this helps.