If you are looking at schools like MIT, the time to get a counselor is now, not when your kid is a junior or senior, because by then your kid’s stats is what it is. For those top tier schools, admission is a lot more holistic, which means ECs,summer activities, competitions are going to be a lot more important.
Yes, you could get a lot of valuable information on CC, but it depends on how much time you have to read through hundreds of posts and sometimes the information is not always complete.