spots documented like your friend has planned
^ A perfect recipe for dissapointment.
I'm sure there's plenty of places you can take him that he'll be excited about without showing a site you aren't through with yet.
I give the areas I frequent an A,B or C rating.
A) I go alone. No exceptions.
B) Might take someone from out of area there to accomplish something we attempted but failed at elsewhere.
C) Borders on being a "community" spot but hasn't quite gained that status yet. (Where you should take him, imo.)
Another big factor is the person in question. I've got friends whom I fish some great "holes" with but would never take them to an "A" site for herps (and vice verse.) In my world there's different levels of access allowed on different fronts. I'm sure you'll make the right call.
Good luck and let us know how it turns out!