On the marine biology side of things, you might consider New College of FL, which is Florida’s public Honors College. I https://ctcl.org/new-college-of-florida/
Their OOS sticker price is around $44K, but it appears that you could get $15K off that, which brings it in under your price point https://www.ncf.edu/admissions/cost-and-aid/scholarships/out-of-state-freshmen/
They are research oriented and have particularly good marine biology related opportunities because of their Gulf Coast location and marine research center. https://www.ncf.edu/about/our-campus/facilities/venues/pritzker-marine-research-center/
Major possibilities for you would include:
https://www.ncf.edu/academics/undergraduate-program/division-of-natural-sciences/marine-biology/
https://www.ncf.edu/academics/undergraduate-program/division-of-natural-sciences/neurobiology/
https://www.ncf.edu/academics/undergraduate-program/interdisciplinary-programs/biopsychology/
https://www.ncf.edu/academics/undergraduate-program/interdisciplinary-programs/environmental-studies-program/
https://www.ncf.edu/academics/undergraduate-program/interdisciplinary-programs/public-policy/
https://www.ncf.edu/academics/undergraduate-program/division-of-social-sciences/political-science/
This could be a particularly good option if you discover that your EFC for the need-based-aid schools is higher than your 30K budget. NCF has a much different “vibe” from the more traditional elite schools on your list, so you’d have to determine whether you’d enjoy that. But it offers a lot of freedom to write your own ticket as far as pursuing your areas of interest, doing research, etc. https://ctcl.org/new-college-of-florida/