Meaning – What Does ‘Beast at Something’ Mean?

"Go meta" refers to the action of doing things in a metaphysical manner, that is to say, in a way that considers the effects of one's actions, instead of simply acting them out. "Meta", in a broad sense, means "self-referential", examining the self and the self's actions while at the same time being that self and performing those actions.

It might help to thing of it as going "plus one level above" and acting as if you were watching yourself doing the action.

In this case, "normal" would be to simply say things that may cause discomfort or be manipulative in nature. To go "one level above", you would openly acknowledge that your actions may have said effects, and yet still act them out.

To "go meta" in a game, you would not just perform things that would get you a good score, but also things "above the game, only visible by an existence beyond the game (the player)", such as completing achievements. These achievements have no effect in the game, but are part of the entire experience for the player.

In this case, aye almost certainly does mean always. For one thing it makes perfect sense contextually. Moreover, the connection with Scottish actually makes a lot of sense. We learn from Morag, in another answer, that aye is still used in Scotland. Even if it weren't, archaic English or Scottish would not be out of place in this song.

The Watson Family lived in the Appalachian Mountains, a region settled by Scottish and Irish immigrants. Difficulty of travel kept them functionally isolated, and the pre-radio music of that region is known for strong ties to old ballads of Scotland, England and Ireland. Here's a great radio piece about this history: http://hereandnow.wbur.org/2014/10/01/wayfaring-strangers-book

The corpus of Appalachian folk music also includes a lot of references to political roles that never really existed in the U.S. - Lords, ladies, knights, kings, etc. Examples abound here: http://www.contemplator.com/america/index.html