The route we ended up taking was:
Aesch -> Unter Chlus -> along the ridge of the Blauberg -> Bergmatten -> Hofstetten -> Flüh
I don't have much of a feeling for the total distance, but we walked for between five and six hours (including lunch).
We didn't do the world's best job of making the trip efficiently, which is why we went back via Flüh instead of Ettingen, but some of that had to do with the disappointing quality of the signage in the area. It wasn't anything like up to the standards we've seen on our other walks. Luckily it's almost impossible to get lost around here because there are walking paths EVERYWHERE.
There were no really impressive photo opportunities, so no landscape/ruins photos, but we did find tons of blackberries. If we had had sufficient carrying capacity with us, we probably could have brought back kilos of berries. This is all that fit in our emptied nalgene bottle + the tupperware bowl I brought quick-pickles in for lunch:
