How much would a B- and a B+ affect my chances for the Ivies/Stanford/MIT?

I wouldn’t panic or worry about it, but I do think you should strategize a little about this. These are heavy classes related to your proposed major, so your question is legit. A couple questions for you:

It appears you took Calc BC from your list. Did you get As in Math? That would be seriously helpful.

Also, did you get Bs in Physics and Chem for first semester AND second semester, ie 4 total? Or just second semester. ie 2 total?

Strategy 1: It appears your physics course was not AP. If you take an AP physics course senior year and get an A fall semester, that would be cool. You could even talk in one of the extra mini essays about how the junior year class motivated you for the AP class.

Strategy 2: As you plan your college list, don’t forget about some good second-tier options for EECS, like WPI, RPI, and so on. You should be doing this anyway.

By the way, I seriously love your three internships, online work, and your tutoring. Those to me are your strengths from your summary.