Actually I've been thinking about this a good bit, and I think the game of baseball could be improved by fan interference. My proposal is this: the offensive team consists of two squads, not just one. The first squad is the usual nine, the second squad is a squad of bikini clad cheerleaders. Cheerleaders would add a lot to the game anyway.
But these cheerleaders won't just be for changing the outcome of the game by getting everybody to stand up. Oh no, they're an integral part of play on the field. See, under the new rules anytime a fan feels like it, the fan can jump out of the stand, run onto the field and tackle any given player. Say Jason Lane is standing under the ball ready to make a catch when wham, out of the bleachers runs Steve Bartman. Imagine Lane's surprise when Bartman tackles him and turns the sure out into an inside the park home run. Of course Lane then gets to pummel Bartman senseless.
But this is where the cheerleaders come in. Not only are they scantily clad, they're jujitsu cheerleaders! Their job is to keep Steve Bartman from interfering in the play! As Bartman leaps from the right field stand, the cheerleaders swarm across the field towards him, tackle him, and pummel him senseless!
Wouldn't that make the game more exciting? I don't know why no one's thought of this before.
The other thing that would improve the game? If everybody on the front row had a cudgel. I bet the Shed could do a brisk business in cudgels.