While having only read through "Gretchen..." a few times, I can't make comparisons.
For me, the most difficult section of "Auf dem Wasser..." was that starting at measure 35 ("Übern den Wipfeln des westlichen Haines ...") where the melody is in the lower part of the right hand with accompaniment in the upper part of the right hand. Sometimes the melody and accompaniment are only a third apart and I found extremely difficult to bring out the melody under the third so close above it.
There are some big, left hand broken chords, ascending and descending, spanning over two octaves starting at measure 86, and while the section is not easy, the notes do fit well into the hand - at least into mine.
Again, the section starting at measure 86 where the melody is essentially in octaves but where, often the accompaniment and the melody break down into two-note phrases, it is very important to get the feel of the 1, 2; 1, 2; fingering in the lower part of the right hand. With the appropriate hand/finger movement this can be relatively easy, but it becomes a stretch towards the end of some of the phrases where the melody note is held on beat 4 and the 1, 2; 1, 2 fingering descends beneath it: a challenge for smaller hands, I would say.
I do like and admire this transcription and return to it on and off, but have not yet even come close to mastering it. But if you mastered "Gretchen ..." then this is certainly worth a good try.
Lots of slow practice without pedal and with some exaggeration of voicing the melody has been my approach.
Last edited by BruceD; 11/29/20 01:18 AM.