In my OOTP game I created two Leagues, no Divisions, divided roughly by the Mississippi River. Top four in each make the playoffs. It also required a two-team league expansion in the West to make things even. You'd create more fan interest with local rivalries (like Yankees vs. Mets or Milwaukee vs. Minneapolis) and you'd greatly cut down the miles players have to travel during the season.
I know players have talked about going back to a 145-game season because more rest equals fewer injuries, as well as more doublheaders but they're 7-inning games, but also recognizing neither will happen.
I favor a near-complete revenue sharing with owners keeping something, like a % of gate receipts, to ensure they have a positive income stream and a payroll cap/floor ensuring players get their 52% of revenue. I know teams have argued "Well maybe our good players are young, so we don't need to spend to a floor" but there's always room to add an expensive reliever on a one-year contract to meet that floor. Also the home manager should have the decision on whether or not the teams will use a DH for the upcoming series, but that's unrelated.
There's also certainly some room to allow more arbitration years, too. Guys like Turang should be making more than $4m.
Unless it can be the Brewers, I hope the Dodgers win the next 10 World Series in a row. Payroll disparity is by far the biggest problem in this sport. Short-term it gets you more eyeballs on the World Series because it better ensures NY and LA are involved, but long-term it's going to ruin engagement. Why should a potential fan in Cleveland or KC or Tampa Bay bother?