College-level mathematics courses are very valuable. Nearly all colleges have a somewhat similar introductory sequence of courses, consisting of Calculus, Linear Algebra, Multivariable Calculus, Differential Equations, and Real Analysis. Thus, there is a good chance that college-level math courses taken in high school will allow you to start at a higher level in college (whether or not you get transfer credit) in mathematics, and possibly expand your options in the sciences as well.
Next I would prioritize courses in the natural sciences, computer science, or economics, depending on your interests.
Courses in the humanities and social sciences may look good on an application, but you're unlikely to be able to use them to start at a higher level in college.
(Of course, you should take AP and IB courses in every field you can.)
Choosing which math classes to study can be one of the most challenging parts of planning your high school schedule. High schools offer numerous math classes, often at varying degrees of difficulty, and it can be difficult to know which math classes will be the best for you and your future.