This is a starter post, ready to replace with your own experiment. Player movement becomes easier to tune when each change answers a specific question.

Change one variable

Try a single adjustment to acceleration, friction, or jump timing. Play the build for a few minutes, record what changed, and compare it with the previous version.

Leave a useful trail

Capture short clips and note the values used. A tiny test scene can be more helpful than a large level when judging the feel of a mechanic.