Your #4 is important. Neither Romney nor McCain made any effort to explain the causes of the recession and its relation to big government programs, including those of G. W. Bush. Reagan would have given the public an economics lesson, but Romney did not.
Neither one of them could do that because that would force them to acknowledge that it would be necessary to cut those "big government programs." Romney and McCain are big supporters of those programs, just as Bush was.
The last two months of this campaign were completely bizarre. We had Romney and Ryan running around (say that three times fast!) campaigning against the massive Medicare cuts in Obamacare, and Obama running around campaigning for a huge cut in U.S. corporate tax rates. On some of these issues, the political landscape has been turned completely on its head.