Interesting post!
I found another way to improve my vim skills and memory was to simply write a wiki page with all the shortcuts / key strokes I learned or used. It has a big benefit for me of anchoring things in my memory.
Always having it open when in vim, referring to it often, adding things, moving things, reorganizing categories was a huge benefit for me.
Here is a screenshot of my wiki page index:
Also, having ones' dotfiles synced on github can be highly beneficial as your vim env / plugins will be consistent between desktop / laptop / office / friends' place.
[Edit] - cosmetics