If you're making that much more than you were full-time (and remembering this is contract work), I would probably try to hire someone on to help ... to keep you

If you're making that much more than you were full-time (and remembering this is contract work), I would probably try to hire someone on to help ... to keep your head in the game I'd recommend you do a feature or two as well as architecture / spec. Once you've got the bare-bones done the new-hire can come on and start learning the code base as there are things to refactor, implement, test, etc. Meanwhile you're still contracting making money and in your free time you're focusing on the "fun" things of software dev.