Looks like it could be a lot of fun.|
I know it's an early stage but some ideas..
-Maybe use a brighter, less realistic textures to give it a more cartoony feel
-The other pigs could be standing watching/wandering around while you're teeing up your shot and clap/laugh/taunt etc
-If you wanted to keep the TNT theme, you could have bombs on the course as obstacles to be avoided
Keep up the good work Doc, will let you know if I think of anything else in the meantime :)