"I think it depends on your personal experiences with each species. "
I meant that as that effects which one you recommend to others as a first snake. For me, I will recommend both corns and ball pythons as my experiences with both are good.
I feel that if you research a snake with care that suits your needs and are ready to handle any specfic behaviours, MANY snakes would be just fine for starter snakes. If someone cannot grasp the simple fact the balls fast, or that corns wont ever just sit there while you hold them, then they need more time thinking about which species of ANIMAL over all they want IMHO