HI,

Not sure if you saw this but the Chimp tracking in Ft. Portal is a great time as well.
If you have time Lake Bunyoni (sp) in southern Uganda is a great experience as well.
Finally the Sseese Islands in Lake Victoria are an interesting diversion. Last I heard there was a ferry. SS Kalangala running from EBB to the islands. Ferry is new and very fast. I would suggest this over the other ferry that runs out of one of the towns south of Kampala.

Best of luck on the trip, Uganda is fun to travel and a little less developed than TZ or Kenya!