Whether to use "awesome" instead of "virtuous" is the question, not the answer. This is the question asked by Nietzsche in Beyond Good and Evil. If you've gotten to the point where you're set on using "awesome" instead of "good", you've already chosen your answer to most of the difficult questions.

The challenge to awesome theory is the same one it has been for 70 years: Posit a world in which Hitler conquered the world instead of shooting himself in his bunker. Explain how that Hitler was not awesome. Don't look at his outcomes and conclude they were not awesome because lots of innocent people died. Awesome doesn't care how many innocent people died. They were not awesome. They were pathetic, which is the opposite of awesome. Awesome means you build a space program to send a rocket to the moon instead of feeding the hungry. Awesome history is the stuff that happened that people will actually watch on the History Channel. Which is Hitler, Napoleon, and the Apollo program.

If you don't think Hitler was awesome, odds are very good that you are trying to smuggle in virtues and good-old-fashioned good, buried under an extra layer of obfuscation, by saying "I don't know exactly what awesome is, but someone that evil can't be awesome." Hitler was evil, not bad.

You think you can just redefine words, but you can't,

That's exactly right. Including "awesome". Tornadoes, hurricanes, earthquakes, and floods are awesome. A God who will squish you like a bug if you dare not to worship him is awesome, awe-full, and awful.

If you think "happiness" is the stuff, you might get confused and try to maximize actual happiness. If you think awesomeness is the stuff, it is much harder to screw it up.

Saying that it's good because it's vague, because it's harder to screw up when you don't know what you're talking about, is contrary to the spirit of LessWrong.

That is, "awesome" already refers to the same things "good" is supposed to refer to.

Awesome already refers to the same things good is supposed to refer to, for those people who have already decided to use "awesome" instead of "good". The "Is this right?" question that invokes virtues and rules is not a confused notion of what is awesome. It's a different, incompatible view of what we "ought" to do.