I played this a long time ago and, with the right practice and previous Schumann exposure I'd had, I didn't find it hard to get under the hand; it kinda reminds me (Chopin's) op.10 #4 in that the overall structure and patterns and actual notes are not that hard to put together (I am not saying the required techniques are the same tho) but getting, and keeping, it up to tempo are perpetual endeavors. As for reaches, in general, break ones that aren't comfortable; long "reaches" in Schumann are usually meant to be broken, it's part of his style.
I worked on this after just having done the Symphonic Etudes, Kriesleriana and parts of the Fantasy and I was just really immersed in Schumann and it was a really energetic, fresh, happy, youthful time in my life so I really related to the Toccata and eagerly attacked it. My teacher, however, didn't share my enthusiasm for the work and when I first played it for him he said "there's nothing I can say about this until you get it up to tempo"-guess he knew that would be the end of that LOL-actually the semester was up then, he took off somewhere, I put the Toccata down and was never inspired to pick it back up but my previous flirtation with it was nostalgically memorable.