Good info, but one thing is missing: Many states that issue non-resident permits/licenses will do so only if you have a license from your home state. I have a number of out-of-state permits/licenses, and I remember having to send in photocopies of my home state permit for many (if not all) of them.
How many of the states you list will issue a non-resident permit to an 18-year old who does NOT have a home state permit?
Also, some states offer reciprocity only for home state permits. (For example, I have a Florida permit. It allows me to carry in a number of states, but a few states that will honor a Florida permit for a Florida resident won't honor it for me because I'm a non-resident.)