Talk to the guidance counselor to see if you can get historical acceptance data for kids like yours. Is your kid a top recruit? He may be able to take fewer APs. What level of college is he targeting? The athletes from our competitive high school who go Ivy/T20 have top rigor (IDP and/or lots of APs) plus high grades.
ETA: Our high school is/was a toxic competitive environment where kids strove for excellence in their pursuits. The actual bar may be lower. Taking 6 of the offered 8 APs and getting good grades seems rigorous enough to me.