I don't have any real numbers to back it up, but the numbers presented here feel really wrong to me. Anecdotally, in my last campaign we played from level 6 to 13, using wands of vigor nearly exclusively for healing, and used up a total of 6 wands in that time frame. Which seems to be a fraction of what your numbers predict. I don't know if the incoming damage my groups experience is just significantly lower than what you expect, or something else, but something seems off here.