The large commercial filters almost always use pea gravel. Supposedly you get slightly better flow without any loss of filtering. Pea gravel is also cheaper than sand. I have never tried it myself since I don't replace the sand.
One of the advantages I could see to doing that is that the pea gravel would surround the lateral fins and keep sand from infiltrating into your pool in the event that a crack were to occur somehow. I don't imagine that it would affect filtering at all. I sort of like the sounds of it, and if I were to do it again I would probably do it, especially since I do get what appears to be sand on the bottom of my pool after the return line. I am not positive though, I vacuum and it goes away. It is not really that big of a bother to me, but if it gets worse I may just have to shop vac out the filter and see what is up.