klipsch cornwall iv upgraded crossovers

I own a pair of cornwalls, amazing speakers they are paired with MC452 power  and a MC 70 tube pre.I play cds only on a yamaha C2100. My question is I hear people talking about upgrades to the crossovers on the corns  and softening the horns with  sound tape . Do any of those changes work,one or the other and do they make it worthwhile. Would like input from anyone who has tried the upgrades and who they used