Am I slacking off too much senior year?

(Wow so this turned out super long, feel free to just skip to the bolded sections at the bottom)

Here’s what I’ve taken already:
Freshman: Honors English I, Biology, Spanish I, World History, Geometry, PE
Summer: health, college and career planning (HS req, not college prep), an AMC10 prep class (not for credit)
Sophomore: Honors English II, Chemistry, Spanish II, AP Euro, honors algebra 2/trig, XC/track (takes up a class period and counts as a class)
Summer: American cinema history through community college (fine arts req for UCs), precalc at CC
Junior: AP/IB Lang, honors physics (basically IB SL), Spanish III, APUSH, AP/IB Calc BC, XC/track
Summer: Art of problem solving (AoPS) into to number theory (online), ends a couple weeks into senior year so there’s some overlap

At my school we have 7 class periods, zero through six. Because sports take up a class period, that leaves me only 6 slots for academic classes. And our zero period starts ridiculously early, closer to 6:30 than 7:00. So I’ve had only 5 academic classes every year so far, but it’s not like I’m going home early, and I take extra classes every summer.

** This is what I want to take next year: IB Lit, AP Econ, AP Biology, robotics, XC/track, and stats at community college first semester then probably an AoPS course second semester. Second semester I’ll definitely have a math and/or engineering course, most likely intermediate number theory through AoPS. **

I wanted to take engineering (weighted) instead of robotics but it’s probably canceled, if it’s somehow an option then I’ll definitely take it. Robotics interests me because I feel like it’s similar to engineering, and since I’m considering a major in engineering I really want to get a chance to try it out. It counts as a college prep class and an academic elective for UC schools (the G in A-G), so I don’t think it’s just some joke class. It’s also part of our technical education program.

** Should I add another class or replace robotics with something harder/weighted? **

Other classes I’ve considered taking: AP computer science, IB physics, cyber security

What about Spanish 4?
Also make sure you have a math course (not engineering).

Yeah I figured it would have to be math, for UC schools the college course counts as a full year even though it’s just a semester, but I’m mostly applying to non-UC schools, so I don’t know how they’ll see it. Since I taught myself math and did summer classes and stuff I’ll have something like 6 years of math when I graduate, does that affect anything? (Geometry, algebra 2 trig, Precalc, Calc AB, Calc BC, stats, intro number theory, probably intermediate number theory).

Spanish 4… I know that it’s good to take 4 years of a language but I really dislike the class (learning a language is interesting, the way the classes are taught is just super frustrating to me). And I don’t know if I’ll be able to get an A in the class, I guess I probably could but I’ve been right on the border of an A and a B a couple times before. Usually when I miss points it’s dumb mistakes, last year I’d get like a 95 the vocab/grammar tests and then 6/10 on a quiz about Picasso or something. I have a 4.0 UW and don’t want to mess it up.

I also just don’t feel like I learned much in Spanish III, I honestly think we had more tests/quizzes on videos we watched or articles we read or songs we listened to than actual grammar. So I worry about being properly prepared for Spanish IV.

Ok so this is my schedule right now:

AP Biology
AP Economics
IB Literature
Engineering/Manufacturing technology (weighted)
Robotics
XC first semester/ track second semester
Stats at CC first semester/ AoPS course second semester

Think taking a STEM-heavy schedule (that I want to take) compensates for dropping Spanish? For what it’s worth the most selective school I’m applying to is MIT and the second most selective is probably Berkeley.