Watching the sprites in vram while the game runs is really neat, and shows a bit about how the game is put together. For instance in Kirby's Adventure, (IIRC)Kirby's walking sprites take up about half the available RAM, and they get swapped out for the flying sprites when he jumps.

Compare this to some of the early non bank switched games where the all sprites fit entirely in memory, with some creative tweaks (bushes are recolored clouds, etc).

It's a bit myopic of Nintendo that on-cartridge mappers had to be necessary, but on the other hand, it's early 80's consumer hardware; it was probably state of the art in the late 70's ... which makes it hilarious that Wario's Woods was released in 1994.