I've always HATED the challenge system.
1 - The whole notion that the onus of getting the correct call being on the participating sidelines is just wrong. The onus should be wholly - not in any part - wholly upon the impartial officials. Whether the term officials pertains to the on field zebras and chain gang and/or a remote video command center, it is the LEAGUE'S job to officiate the games, it is the teams' job to just play the games.
2 - Related to point 1. In the final 3 minutes and overtime the challenge system is moot (except now for PI), only the command center can initiate a review. Why can't they just do that for the first 57 minutes too?
3 - Make replay a tool available FOR the on field officials instead of always pointing out their errors. Two guys thought he was in, one thought he was out, but did he still have possession yet? Let the referee call up the booth himself. Why not?
4 - The hanky system invites frivilous challenges. If there's a minute left before the 3MW, why not just throw your challenge before it expires? It's worth a shot, costs nothing. Chamblin did this on Sunday. Didn't have much chance of winning it but with PI incidental contact to one person is a blatant push off to another. Could get lucky. I remember Buono throwing a really stupid challenge in the 2006 WF just to ice the kicker in the last minute before the half. Riders caught a pass near the sideline well short of the first down. 3rd and 5 Barrett sends out Congi to kick from about 20 yards away. Just as they snap the ball the hanky drops. Buono wants an incomplete pass to make it a 25 yard FG on 3rd and 10. 30 seconds to half time, might as well burn that challenge flag that's about to expire in a game that was a 4 score blowout in the 2nd quarter! Stupidest challenge ever just because of the challenge system that should not be there in the first place.
The burden of justice should be 100% on the officials, 0% on the teams. It's not fair to the teams or the fans to do otherwise.