MAGIC FIND on charms and maybe belt only?

I think charms are not very exciting in its state. You get to endgames then easily fill the charm slots without much effort or thoughts.

If you move item rarity / magic find there only then they will be more interesting to loot and hunt for.

Also consider doing something like charm set item system from d4 in the future. I think that would be cool without locking away all your item slots too much.