If they want to improve pace of play I think they could perhaps start some program in the minors where they encourage pitchers to speed up the amount of time between pitches and encourage hitters to stay in the box. Then after this has had some time to settle in, say 10 years down the road or something, they could put a timer on pitchers and perhaps not allow batters to leave the box. It's unfair to expect veterans who have longstanding routines to start doing something different.
But I wouldn't even do that. Frankly it's all a bunch of BS to me. I like the game and don't really care if casual fans lose interest and the sport slips to 3rd or 4th most popular in the US. The game is slow to develop between plays and that's just the way it is. Without changing the game play maybe they could give each manager 3 timeouts to be used for mound visits by the Catcher, pitching coach or manager (pitching changes aren't time outs). If you lose a replay challenge you lose a timeout.
I think creating better ballpark experiences and finding a way to promote its stars better should be a focus rather than pace of play. Moving to Under Armor was a nice little step. I like that they are getting more buzz for the draft now, that needs to continue. I think the All-Star Futures Game format could be changed to make it a Rookie big leaguers vs. Minor leaguers. Or maybe they just leave the Futures Game the way it is and have a Rookies vs. Sophomores game like the NBA does.