IMO, the Scherzo over the Beethoven any day! Its much less overplayed than the Beethoven, and the 1st mvt of the Beeth is very easily screwed up. Its extremely difficult (not technically, but tone wise, and emotionally taxing) and not many pianists can pull it off properly. Consider it carefully before deciding.
Work on mastering one piece at a time. You'll find that you master the pieces alot quicker this way, and develope a huge repertoire in no time. (devoting 8 or more hours a day, to one piece, and getting it perfect in 2 or so weeks, I find is alot more productive and encouraging to me, than to work on a few, and never really perfect any, and lower my self confidence) Also never tackle something that you know is too difficult for you. Also doesnt achieve much