MLB recently held a think-tank meeting to improve the way baseball is played. They concluded that full-on instant replay is the way to go, calling a consistent strike-zone is important (are you sure?), and pitchers and hitters can't take too much time between pitches. While I agree with these, there are a couple that would be easier to implement and improve the game in a far more natural way.
1. Raise the mound
The last 42 years have seen several rule changes, and every one has favored hitters. After 'The Year of the Pitcher' (1968), the rule makers tried to re-balance the game in the following years, but went way too far. They lowered the mound a full five inches (from 15 to 10) in 1969 and added the DH in 1973. In addition, bats got better, ballparks got smaller, and balls got juiced*. By re-raising the mound to a nice, even foot (15 inches is too large a swing in one year - if 12 inches doesn't make an impact, then go to 15) it would allow pitchers to not only get more plane on all their pitches, but would make them more comfortable throwing hittable pitchers (because they would be tougher to hit) and reduce injuries (due to less effort being exerted and throwing fewer pitches). There wouldn't be so much nibbling and we'd get to see more balls put into play (which I find more interesting than strikeouts and walks).
You wouldn't have to impose silly rules like 20 seconds between pitches or batters can't step outside the box. Raising the mound would be an organic way to improve and speed up the game without imposing more rules. The higher mound worked just fine for 66 years before 1969.
MLB wants to have its cake and eat it too. They want all the offense of the past 15 years while reducing the length of games. Sorry MLB, that won't happen until pitchers regain some kind of advantage.
2. Balance the schedule
The Yankees will play 76 regular season games (almost half) against only four teams: the Sox, Rays, Jays and O's. To me, that is boring as hell. Playing 19, even against our biggest rival, is tiresome. Each games loses a bit of luster because we see them so often. And never mind the other three teams in which there's essentially no rivalry to speak of. Do we really have to see the Tampa Bay Rays 19 times a year?!**
To account for all the divisional games, we'll only see teams like the Indians, Tigers and Mariners six times this season. I enjoy seeing different ballparks and different players rather than the same stuff over and over and over. How many damn times do we have to see Kevin Youkilis' chia pet, or listen to that stupid cow-bell?
A balanced schedule would also give us a greater sense of the best teams. The Rays may very well be as good as any non-Yankees-Red Sox team in the AL, but since they have 38 games against them (as opposed to 12 for a non-AL East team), it could conceivably make a 10-win difference.
What changes would you make?
* I remember a great article (that I can't find now) talking about how baseballs aren't necessarily more lively than in the past, but the rules for baseballs are now stricter, keeping them within a smaller range of 'liveliness' (generally on the higher end), while there used to be a wider range, ensuring 'deader' balls would occasionally be used.
** The real reason behind the unbalanced schedule is purely Yankees-Red Sox. Getting that matchup 19 times a year boosts TV ratings (aka, revenue). MLB really doesn't care how the unbalanced schedule affects the other 28 teams, as long as they get the Big Matchup 19 times. They have to enforce the unbalanced schedule for everyone so as not to look biased.