Let it be totally interactive and the fans vote to uphold or overturn the call. No refs, no league office, no nonsense in the booth, just BAM, everybody has say 5-10 seconds to vote.
Benefits: near-instant results, the game can flow smoothly again like in the old days, getting right back to the action, and, best of all, the teams with the most rabid fan bases can nix calls that go against their team. Talk about an incentive to watch! And you know dang well advertisers and TV types would jump all over this.
Who decides what plays to review? Not the refs. Give each coach a certain number of freebies. Sure, Bama and others would try to stack the deck, but they'd also get flooded with underdog voters from all over the country who would love to see them go down.
Now, if instant replay ACTUALLY WORKED, the above idea would be ridiculous. But as the years have gone by, I've seen as much incompetence or outright chicanery in the reviews as there ever was in real time back in the "day." At least the above notion would speed things up and throw some fun into what has become tedious idiocy.