When your son is a senior go take a look at the freshmen and you'll wonder how most of them could ever get to be the size of the seniors, but they do.
You seem to have a pretty good strong program there if I've got the right school so they must be doing something right.
Your son is in a great position if he's made varsity at a good program as a freshman. Don't sweat the small stuff and don't be patronizing toward the kids who aren't there yet. We've watched kids who were on the national stage at 12 and 14 years old and are still doing fairly well (i.e. D1 signs) get left in the dust by kids who were unknown back then.