I'm all for shortening the game; don't like waiting to watch our game because the previous game in that broadcast timeslot has run 1/2 hour over. don't like getting home at 2 a.m. after a 7:40 p.m. kickoff.

I've seen booth-reviews decide the outcome of games. CU Boulder win in Autzen in 2016 because a spectacular TD catch by Buff WR was first ruled incomplete (on 3rd & long from midfield). and then later that year the Carrington TD catch at the end of the game in Rice-Eccles (first ruled OOB and INC).
those things need to be got right, esp now with all the $$ involved.

I would like to see them limit the scope of what can be reviewed. targeting, for example, takes way too much time. I know the intention is good; to protect the players. but helmets will collide in space during a football game. it's like they're asking the replay official to read the mind of the player. almost all of those helmet-to-helmet incidents are unintentional. 
maybe grant coaches two or three challenges and don't review anything unless the review is initiated by coach's challenge?

MLB has had success reducing extra-inning games with the new runner-on-second rule. CFB tweaked the OT rules a few years back; now one play two-point conversion play starting 3rd OT. hope some of these other changes will be successful.