Granted I haven't read the entirety of this thread yet, but I'm deeply grateful to see that there are actually still reasonable, rational Republicans and/or conservatives out there. You don't see many such individuals actively participating in North-American politics anymore.
From what I've seen north of the border in the last three elections I've been old enough to follow, the issues that are most bitterly disputed and used by both American parties to vilify the other are the major social issues - specifically things like abortion, marriage equality, etc. Matters that one would think should be easily resolved by a basic examination of America's foundation are dragged out, overblown, and used to paint the other guy as hating their country and/or its people.
So, in my mind, the single biggest thing modern right-wing American (and even to a somewhat lesser extent, other western) politicians need to do to become feasible and electable again is join the 21st century on the big social matters. There reaches a point where you're no longer the nation's social conscience, you're an impediment to much needed progress and advancement. And the only way to really avoid becoming such is (ironically) look backwards, and accept and promote the separation of Church and state as outlined by their own Constitution.
The United States were founded on the basis of morals and ethics that happen to be shared by Christianity. That's purely because Christianity was the predominant religion of the generation of European colonists who founded the nation. The same ethical guidelines are also shared by countless other religions throughout history. But the Union was not founded as a Christian state, and thus should not be governed by Christian law. The separation of Church and state is a massive part of what enables the very freedom of religion and expression that's been a staple element of American culture from day one, yet the same right-wing groups that cling so tightly to the "founding elements of [their] great nation" do all they can to impose their own religious beliefs on the government and thus the rest of the nation. I've never understood how one can cling to two such conflicting ideologies simultaneously.
Consider for a moment the matter of abortion. There has yet to be a sensible, non-religious argument for outright banning abortion. And these arguments and beliefs are perfectly fine, so long as you can freely admit that you oppose it because of your religious beliefs. But when you try to force the government into legislating and "validating" (for lack of a better term) your religious belief by outlawing the practice in line with your beliefs, you're intruding on the religious and expressive freedom of those who do not share your opinion. But by permitting and legislating the practice, no one's rights or freedoms are being compromised - those opposed to abortion are not going to be forced to get one. And the very same applies to the topic of marriage equality, as well - permitting open and equal marriage opportunities intrudes on no one's rights, but introducing legislation against it does.
Once the Republican party comes to terms with this basic fact - or, alternatively, those that do understand this toss out the crazies that refuse to come to terms with it - then the matters that really matter, such as the country's massive debt crisis, can be properly discussed and resolved by both parties, and an action plan that both parties have made compromises for will be able to pass the desk of any President, regardless of his party.