I didnt overlook your post you overlooked the VPs duties, the VP isnt a policy setter. Also its not a politicians job to be interesting or exciting, its to govern effectively. If you pick a VP based on what will energize your base and not whats best for America then you dont deserve to win. People wanted fresh faces in 2008 and 2010. They got them and now they are extremely disappointed with them. Do you really think they want to go for a 3rd round of disappointment?
In most cases, the VP is not a policy setter. Dick Cheny was the exception rather than the rule. In other words, it is up to the top of the ticket to decide how much influence and what type of policies the VP would be entrusted to. If McCain had won, Palin would have been given free reign to use her expertise in the energy sector cause she is more knowledgeable than any of the duds on the hill. That would have probably been her one and only policy gig. Strength's: Portman's would be a budget wok. Kasich unemployment and jobs, West defense, Rubio a young fresh face to garner Latino votes.
McCain was a piss poor candidate and there was a great deal of anti-Bush sentiment plus white guilt. Massive job losses did not help either. So, it was not only a question of a fresh face, it was a combination of negatives that added up to a Democratic victory. Palin did energize the base and IMO McCain would have lost even worse had he not picked her.
I don't follow you with the the 2010 campaign. The Repubs took over the House and picked up a few seats in the Senate. It was not a rout like 2008. I agree that some of the Tea Party candidates have been a disappointment especially those voting for more spending. Repubs need to win the WH and the Senate. We can only hope that they get back on the right track.