Seems like Cell is doing the Macarena and Babidi is falling, guess he's afraid of heights.
Yes, it does look crowded at the bottom but you have space on the upper side, try giving a bigger height boost for the larger figures at the back and arrange them in a way where it's a descending order. Definitely not a pro tip but couldn't resist commenting. You have a nice collection.
I've got cell in that fighting stance that he has sometimes...
Yeah, Babidi falls over a lot. He's quite good at it.
I'm either going to gets some risers to do what you suggested or just split them up among multiple shelves. I'm not sure yet.