Regarding your lack of improvement, you only keep making excuses.

Crawl, walk, run;
from level to level get better.
(The meaning is that when learning something new, you have to proceed from step to step: baby steps first, then bigger ones.)

By scaling the highest wall, he proved to us that his climbing ability had improved.

I'm delighted that your Na'vi is improving every day

Please improve this explanation. It's not at all clear.

The situation with the Skypeople hasn't improved one bit.