I think the problem with Li'l Bush is that his public persona is so hollow and one note that there's not a whole lot to work with, not to mention that said material has been mined several times over already with whatever other character parodies there have been over the years. Though to its credit Kari Wahlgren does a voice or two for the show.

l'il Nixon would be exponentially more entertaining.

"now we're going to invade Kampuchea"

fun for everybody, really :)

ETA: Anybody catch Robot Chicken's "Little Hitler" sketch? Dios mio that was funny