What you're advocating is the GOP becoming Democrat-lite. Mark Levin said it best. All the emphasis, particularly on the Senate side, is on the conservative/Tea Party guys who lost. Yet, little was said about all the "moderates" (who did some of the very things you suggested) that got smoked.
Notice that, 8 years ago, there were almost no talks from the Democrats about taking your advice as it relates to hateful views about conservatives, Republicans, and Bush. They didn't stop the "raise taxes" mantra. And they had no problem being obstructionists.
I think BUSH caused the fall and the GOP in the last 4 years increase the speed.
What i am advocating mainly is the GOP distance themselves from things vulnerable to spin like "End medicare", "Abortion is murder", "If taxes are lower more people will be employed".
And, their obstructionist attitude didn't bode well in tough economic times.
Hard core conservatives principles aren't accepted well when the economy is on the sate its in.
"Cut spending-lower taxes" is not an attractive deal for people who are struggling. To sit here and say increasing taxes for people that make 250k is unfair doesn't sit well with the family that makes only 90k per year or less.
"Spend smarter and give tax breaks to companies setting up manufacturing in the USA producing jobs" would be much better.
Its all about the paridgm of how people see conservatives.