Got stuck on this level. I liked everything that came before it and, actually, I've found the levels with teleporters on every surface more enjoyable because they encourage thinking about phase, cycles and displacement instead of avoiding obstacles. The level that came after Alan's screenshot was quite boring, for example.
Everything else is good, as others have said, the introduction is especially great.
The level I am stuck on is just really hard to think about and I am done with puzzles for today, will try to continue later :)