Both are great starter frogs. My auratus are actually pretty bold, I know many people say they are shy, but I think it depends on the environment, morph, and individual frog. Tincs are great frogs as well, and there are many color morphs to choose from. The only problem with tincs is the aggression. As mentioned before, the tincs do best in pairs because they can be very aggressive if kept with the same sex, especially females. Just watch out for competition as they mature or buy an already sexed pair to avoid this.
Bryan