Can't speak for you, but I would mend. I like to get all the "garbage" chores (such as mending ... YUK) done before I do the fun stuff ... the fun stuff is sort of a reward to myself for having completed chores. It seems the only way to get the chores to go away is to "bite the bullet" and do them.
Several helpful reminders about the needed shelves should do the trick. Guys see helpful reminders as nagging and they hate to be nagged.