His idea for a replacement is very gimmicky, especially considering the final couple of minutes where a team is more likely to be successful with the make it take it style than recovering onside kicks.
I've thought about Belichick's comments a few times, and even though I kind of agree, I don't know if it should change. Even if most kickoffs are returned within the 25 or 30, I don't think you can really take away the chance at an extra 20 or 30+ yards and just place it on the 20 or whatever.
My frustration with it though isn't exactly the kickoff itself or the chance (or lack of) that one will be returned beyond the ~25, but with all the stoppages. When I have a game recorded on my DVR, I generally FF from the time a team scores until the next 1st down, skipping the possible delay while reviewing the score, then the EP, commercials, kickoff/return, and commercials. It's basically 5 minutes of pointless football and commercials that usually results in one easy point and the ball at the ~20-25 yard line.