We do something similar, only the fire stays inside and above the pumpkin rather than outside. Same general idea, though, with the roll of TP and kerosene. Add an old, grungy bucket for soaking the roll and some long handle pliers to avoid getting kerosene all over your hands. We don't pour it into the pumpkin, but that does mean we have to change the TP roll a few times as it goes out. Will have to consider this method. The hand sanitizer looks pretty good, though it obviously doesn't last very long and I certainly wouldn't be squirting it onto an already flaming specimen.
Works great with a really large pumpkin. Or one that has partly rotted and caved in at the top - push that in so it make a cave and the flames do some neat swirling since they can't go straight up. (What? I let a pumpkin go too long. Had to do something with it.)
Also, we do keep ours behind the fence in the back yard - visible to guests, but not reachable.