If you owned a team and were building a new park, what little knickknacks would you insert into your park to give it character? Like SF's right field fence going right in the bay, Houston's train thing, Detroits hill and flagpole in center field, Arizona's swimming pool in the bleachers, and so on.
The one thing I would do is have a fairly deep and high center field, like a 10-15 foot tall wall. But in front of that, I'd build a tiny "juror's box" seating area for no more than 20 people right at field level with a waist or chest high wall. These seats would be auctioned off one hour before game time each day. These would be the most unique seats in all of baseball. You'd see every inch of the field, plays happen right in front of you, to your left and to your right. The centerfielder could take a running leap into your lap at all times. You wouldn't want to leave your seat all game, it'd be like sitting on the field itself.
That, and have a signal that jammed cell phone calls. I'd turn it on whenever the game was going on.