I wanted to know if there's a way to edit certain things about a class for houserule type things. In particular I'm looking at allowing a paladin to take two weapon fighting as a fighting style, but other such things are also what I'm interested in (basically things that can't be edited by just making a homebrew subclass) 

There aren't any seamless/clean ways yet, but there are janky work arounds.

 You can make a homebrew feat that gives the benefits of two weapon fighting and then not take a fighting style from paladin.