Thanks to everyone for the replies! As I touched on earlier, I only recently started preparing for college, so any insight is very helpful!
Right off the bat, I forgot about English senior year—I’m definitely taking 4 years 
. In my school, AP Lang and Lit are generally offered in 10 and 11 respectively (IDK why), so I would be taking Honors English 12.
I haven’t done a ton of school research and wasn’t super aware that Ivies didn’t have top engineering majors. To clarify my situation, though, I will need (and, with a negative estimated SAI, would qualify for) substantial financial aid. I talked with my GC about this, and he said that, given my strengths, I try for Ivies or other more selective private schools that give more need-based aid. I’m not sure if this is good advice…?
I am first chair violin in the school orchestra, and am at the level where I expect to continue qualifying for all-district orchestra outside of school (for my EC list). I guess it wouldn’t hurt to keep taking orchestra for the easy class, though.
Regarding Spanish, I guess it would probably make sense to take it. Some of you mentioned that I would need to take more years of Spanish, though. My school doesn’t offer AP Spanish Lit, so what could I take afterwards?
Anyways, I get the sense that, while I might be overdoing it, I definitely won’t be undergoing it? I only ask because, I know many kids who are and have taken similar numbers of APs in my area, and I don’t want to be behind. Thanks for the help again!