You're right, Farlander, the whole high ground thing was stupid.

I was thinking that the duel could end when that crane goes over the lava-fall. Obi-Wan swings to the riverbank, the music climaxes as the crane goes over the lava-fall. For a moment, we think Anakin went with it. Then he comes lurching at Obi-Wan who responds with the limb chop.

Another thing about the ending of the duel: I didn't really like how Obi-Wan just left Anakin there. Maybe we could make it look like the riverbank is breaking down, and Obi-Wan has no choice but to retreat and watch his friend burn.