I love this game, it has so much charm. The hearing aid joke was so good.
However I think there are some issues, like the knees hurting mechanic doesn't really add much, it just adds downtime. Perhaps make the player slower instead? And add a granny walk that you can use when your knees don't hurt?
Oh and unless I'm missing something I have no way of knowing if the granny will use pull, push or hold, so it just becomes a dice roll at that point and doesn't feel very "gamey".