Core + Mutants?

Hey all. New solo player here.

I was wondering what the general thought process is of going from the core set to the 3 mutant focused expansions is?

For budget reasons I can't buy everything or even most things but I do love xmen and think I'd enjoy those expansions and packs more.

Are these good expansions? Would it be too hard to start the mutant stuff would just a core set?

Thanks all. Advice welcome!