We attempted to climb both Ancohuma and Illampu; the results were success on Ancohuma and only partial success on Illampu. I made a separate page for the Northwest Face/Southwest Ridge (the standard route) in the "routes" section which you have to click on in the left-hand column.
Your descriptions are exactly as I remember it from July 1999, when we climbed to 50m from the summit. Your description of the approach to Aguas Calientes is very good - better than the guidebook. Well done.
D