At this age, the worst thing you can do is turn your nose up to your son playing PAHL. With the right organization and right coaches, your son will develop both from a social and hockey acumen standpoint. There's lots of anabolic parents out there that feel their kid needs to wear the extra A, don't fall into that trap. Convenience, cost and extent of travel are also things you should really consider.
Plenty of years ahead to consider AAA hockey as your son develops.