is it going to be a problem when I remove all my ceramic rings and switch over to bio balls?
Let me ask a question. Is your current filtration not able to handle your bio-load?
If everything is working fine then don't change a thing. (if it ain't broke, don't fix it) However, since you're asking, I'm assuming that everything is not fine or that you are about to increase your stock significantly and are worried about your potential bio-load...
my personal opinion is that if you are worried about bio-load... get another filter, and use whatever you want.... bio-balls, ceramic rings, pot scrubbers, leggos, those tiny army men figurines...
Or if you have room in your current filter... add additional bio-media to it (bio-balls if you want some variety)
I would not suggest removing any of the ceramic rings that you currently have.
Warning: I have never used leggos or tiny army men, nor have I ever heard of anybody seriously using them (I have heard people bring up the possibility)... but as long as they don't leach out chemicals or harmful substances into the water (which I'm not sure if can figure that out) I don't see why they wouldn't work.