Honnestly, my congratulations! I am in the same boat as you and 3 years is a long time especially when doing big/risky refactoring. I did my refactoring mainly to manage my application state, I really thought I would never gonna make it (and I was working in Swift, in Javascript it would have been nearly impossible to do the same thing...). But it was worth every second I spent on it: code is the main value of independant developers, so we should take great care of it!

I wish you good luck with your project and hope it will work.