I think your concerns are universal. However with your son being in the 7th grade I think you have more than enough time to get a feel for all the schools and the coaches. You are fortunate in that you do have a choice in selecting a high school. In our state the students are geographically zoned for a particular school and while they can transfer to magnet schools based on academic achievements, athletic transfers are not allowed under any circumstances. We must play the hand that is dealt us.
You are concerned about the selection process:
i don't want him to go to a hs and not make a team because someone's mom or dad is friends with a coach.
Newcomer suggest a solution to the selection process:
Often, the high school coaches are involved in these camps and get to know potential players. It is always nice to be a "familiar" face but a surprise is good, too.
Maybe you can be a "better" friend to the coach ---
I admit I had the same feelings as you when my son was pre-high school but I also had confidence in my son’s talent and the baseball coach’s ability to evaluate talent. I decided there were things I could control and things I could not (or should not) control and I let the chips fall where they may. With your son attending a religious based high school one would assume that fairness in player selection would be much better when compared to that of public school.
Fungo