There aren't going to be any big gains on punt returns, unless the opponent really messes up the punt play.
Brian Kelly insists on using the punt-safe formation, where it's done to guard against potential punt fakes, while maintaining coverage. There's not much real blocking going on the return, other than a couple of chips, and you'll almost never see the "wedge" of blockers forming.
Maybe if two or more folks on the punting team fall down, there could be an opportunity for a decent punt return, but that almost never happens.
To put it this way, you could put Rocket Ismail in his prime as the returner, and you'd still have very similar results, except when the opponent screwed up badly.