The playing of the game isn't the problem. It's all the useless crap that happens when the ball isn't in play. Warmup pitches for mid inning pitching changes, batters stepping out of the box and adjusting every piece of clothing and equipment between every pitch, pitchers taking 30 seconds to decide which of their 2 or 3 pitches they want to throw, replay reviews that take over 5 minutes. Put an end to that crap and you'll make some headway but for gods sakes leave the actual playing of the game alone. No limits on pickoffs, pitching changes, shifting, etc. I play adult baseball in the summer. Our 9 inning games take about 2 hours with the same rules as MLB, doesn't matter if it's a 1-0 game or a 10-9. Somehow we can pull it off.