I suggest majoring in a subject you enjoy and, presumably, one in which you will do well. Success in life is more than getting that first job. You have a mind that needs fostering for many years ahead. Enjoy the journey!
UCSD and UChi are great schools, but they’re not LACs.
Environmental science, biology, and statistics (in the math department) are usually readily available at most LACs - so I’d encourage you to register for a class in each and see what you like. Environmental science sounds like the best way at an LAC to tie most of the threads together into your interests.
If you want major in something that you really love but also hedge your bets by double majoring or minoring in something that will increase employment, then math or economics are your best bets. You can always get into a graduate training program with math or econ.