Hard to put the lipstick on this animal to make it look better... Curious to know if those avg game lengths are just time of play or do they include time on air (e.g. TV timeouts + revenue)? Still those stats mean nothing without knowing MiLB avg game lengths. The problem though is transitioning whatever it is you think you did in MiLB into MLB.
Realistically speaking would any of these adjustments really work in MLB? I cannot imagine limiting pitcher actions would do anything to drastically speed up the game. That papers over only a small percentage of wasted time. The most wasted time is at-bat - throw strikes and swing the freaking bat. Whoever invented working the count ruined the game.
Want to really speed up the game - start it 2 hours before sunset, have no lights, and pay by the inning ;-)... If a HS game can take that long for 7 innings with non-pro players, imagine what the pros could do! I had a JV game take 1h 40m last week - the pitchers threw strikes, the batters swung, and the fielders made the plays.
Why would I prefer to go to an MiLB game - well let's see - cost, attitude, desire, time, atmosphere, entertainment, etc. Those are players that "want" to prove something, they aren't making absurd amounts of money and they don't act like it's all about them.