My heel felt OK yesterday so I went to Aikido class, which was a weapons class so I felt it was less of a worry.
I finally got to try out my Bokken at practice and it turns out it is just the right size. FYI if you hold the bokken where a tsuba (guard) would be if it had one, then drop your arm to your side, the tip of the sword should just graze the floor. And for me it was perfect.
I could not find exactly what we worked on in a YouTube clip but the above video approximates what we did.