Often in maths you build higher and higher abstractions until you've finally succeeded in an abstraction high enough to encode the very axioms you started with, at which point you're back where you started, if a little wiser for the journey.

At this point I'm fairly sure going deeper (or higher) in mathematics is a dead end, you should instead try to go sideways, to the 'ground level' questions that aren't answered yet, or to the questions that aren't yet mathematical.