All those things you say we cannot re-elect Obama for, are things Romney would very probably do under the banner of Republican, though his causes might be different -- he's a big believer in global warming, for example. You have your eyes squeezed tightly shut to what Romney is, and are seeing him only as you hope he'd be. You are also squeezing your eyes tightly shut to any role conservatives in Congress, increased in number and motivated to keep right by the clear rejection of Romney, would have in opposing Obama. So you reach your conclusions based on incomplete factors.
Romney isn't a risk. He's a sure bet -- for making liberalism more powerful in both parties and making conservatives and conservatism in the Republican party weaker.
With my third party vote, I forfeit any say in influencing whether or not we get Obama or Romney. What I am voting for is to join the millions of Americas on both sides of the aisle who are disgusted with both of them, and pray that the next president is so weak politically that he could only muster a little more than one vote in three because of bleed-off to third party candidates by thoroughly fed-up voters. Heaven knows that both Obama and Romney are so weak that this could actually happen in 2012. It's a Hail Mary pass, but it's the only play open to me -- Romney is off the table for me in every way, from moral to political. I refuse to vote against my own spiritial and political interests, and a vote for Romney would be just that.
Regardless of how the electoral college vote worked out, the popular vote has the potential of putting the next lemon president -- and he will be something more than a lemon -- on defense. It's the best any of us can hope for, because no matter how many boogie men you shake at us, no matter how many scary scenarios you present, the fact remains that as president, Romney would make liberals more powerful in both parties, and the fact remains that Obama would do the opposite, whether he meant to or not.
Well, if you believe that Romney is 100% absolutely certain to be just as bad as Obama on 100% of the issue, then I suppose your vote makes sense. I don't believe that, so I'm casting my vote differently.
Third parties won't total 5% in this election. To the extent people don't like either candidate, they simply won't vote, which won't affect either candidate's ability to get a majority of votes cast. You can certainly control your own vote, but I think your hope/expectation that a significant number of voters will emulate you is wrong.