"Obamacare was just a Heritage Foundation plan" is exaggerated, but it fundamentally is the conservative approach to establishing a healthcare system with a functioning individual market, with some but not too many liberal sweeteners. If you make it "more conservative" you are going to make it shittier and more expensive.
They can't come up with their own version of health care that people will like more. The best hope is they'll accidentally discover something like Medicare buy-in and decide it's the true conservative approach, because they can be stupid, but that is unlikely.