After attending the 16 inning game between the Boston Red Sox and the New York Yankees (the best rivalry in the sport), there are three things that I think the MLB needs to do today speed game play and make the game more enjoyable for fans.
1. Revise the review process
The league is just too slow with reviews. Teams have too much time to decide whether to request a review and the league takes way to long to get umpires the call during the review process. There also isn't enough communication to the fans - those paying $100s to attend games live - when a call is upheld or changed. Give the ump a mic and require him to explain the decision on the field... The review process just needs to be faster, one announcement to the stadium - instead of sidebar conversations with each manager - will speed up the game and keep fans informed!
2. Require pitchers enter the game ready to pitch
Unless coming into the game because of an injury, pitchers should be required to enter the game and start pitching... no more warm up pitches on the mound - that is why there is a bullpen!
3. Limit mound visits (player visits and coaches included)
With the exception of changing the pitcher, the catcher (and other players) along with the coaches should only be visiting the mound on occasion. Multiple visits to the mound during each inning is destroying the game and adding too much waiting for fans with short attention spans. Similar to timeouts in other sports, the MLB needs to only allow teams to visit the mound a few times per day.