I always thought it would be cool to have some sort of primitive musket in this kind of RPG. Kind of like the Airship in Icewind Dale. Crazy Inventor, Crazy Invention. It could be slow loading, kinda scary once it gets going. There could just be one in the world, so a quest would have to be involved. I just don't have the knowledge or the means to do that kind of thing myself. !!!! !!!!
I had a rifle download for Morrowind towards the end - used the crossbow action and the bullets came from the arrow aimation - so I guess you could make a musket in Oblivion.