a bed of CC is not a sand bed, and does not have near the same effect. LS holds bacteria better and if deep enough, will reduce nitrates. CC is really just there and really does little more than hide waste and produce nitrates.
there are different schools of thought on this, but that is my .02
IMHO, it would not be worth it to change substrates unless you were to go with a DSB, concidering the stress it will put on your livestock. I recommend doing a search for "DSB" and reading up on the subject. there have been many, many, many posts on this topic.