Yes, the MidAm site states explicitly that "higher ranked teams will receive more spots at evaluations", which makes sense. I believe the 09 group will be split up into 8 teams, which does seem like too many kids to evaluate in such a short period of time.
You cannot chose who is attending based off of stats, because of the discrepancy in the level of play across teams. In theory, the harder the schedule the more difficult it will be to put up numbers and vice versa. The kids on a team that faces stiffer competition should not be penalized because of that just as a players on a team that plays a weaker schedule should not get a boost.
Evaluators won't be able to see who the "right ones" are in that short of a time period. The evaluation is normally very, very game heavy, so they are looking for the kids that perform the best in game situations. I like this format because it eliminates the players that focus only on what they learn in skills clinics and are great at stick handling through cones, but don't know how to really play in a game situation.
Nothing is going to be perfect, but at least this format makes sense.