This post by Matt Yglesias shows why there is no incentive for GOPers to develop any policy ideas whatsoever, apart from lower taxes on the rich, of course.
Various businesses would approve of this or that policy change, but the only one they all agree on, and thus the only one that gets the giant pile of Chamber of Commerce campaign cash, is lower taxes for business owners. Ironically, this is an idea that, given today's tax rates and economic situation, is bad for pretty much every business in the country.
Why would a business owner take money away from someone that was about to spend it by buying the business owner's product? It's crazy, and yet all the incentives are aligned to encourage GOPers to remain in this policy black hole. Leaving, and say, pushing immigration reform will only prevent you from getting re-elected.