You can prevent bouncing as the morph ball by unmorphing and morphing as soon as you hit the ground. It takes two frames and is a bit faster than unmorphing and then falling. You seemed to do this already.
If you do a one frame jump some time before falling, you'll fall a bit faster. It's best for long falls, I've noticed. It can be used in that first long fall where you're destroying blocks by jumping a bit before the brick is destroyed.
The short jump can be used to help you be more precise on taller jumps when an ordinary jump would overshoot you. Otherwise I'd go for a tall jump since you ascend faster.
I too have a
test run. It goes up to the first metroid. It appears you handled some jumps better than I did.
The important thing about metroids it would seem isn't their speed of death, but rather how you can herd them towards the exit. That's why I didn't attack that one as soon as possible.
Are you going to be using
secret worlds for this? I'd like to see how they can used used, and if there are others that are unknown. The select glitch could also be used to
get some obstacles out of the way, so some non-secret world applications could be interesting.
Remember that switching between weapons holds the game up for a frame. I think this may screw with the buffers causing the glitch, but it also means you shouldn't switch unless you absolutely have to.
Edit: I also have to wonder which of the three ice beams is best to collect. It's not needed immediately because of bump jumping, but it's needed nonetheless.