Thanks :) Falling is in plans, although that will be available on an option (most likely on by default + off via info screen while loading).
At the moment I do not plan to have climbing :(
Climbing could only work in very specific places. Adding climbing would make it possible to go into shallow drops but only if you would have a big enough playarea. For most of the people, the drops would be gone as if you could fall there, you would have to be able to move freely there - requiring playarea big enough to contain the whole place.
I might still add climbing but it would be in a very specific place/section rather than a part of the gameplay loop.