That's a really neat idea.
Being able to sort by some of those would also be helpful (e.g. Sort comments by 'exceptional insight', don't show me comments with >2 'overly aggressive'.)
You mentioned an alternative comment structure in the features post. Some of the value of that could be achieved by a 2nd tier vote saying a comment is a key consideration (e.g. "This is a crux"), and being able to sort by that.
Yes! I often put this lesson down in my top three most useful things learned at CFAR.
In the pair debugging sessions, if I came up with a solution to my partner's problem, straight up presenting the solution rarely worked (it was often wrong in some way, and then we were conversationally a bit stuck). However, when I asked leading questions around where I thought the solution could be (e.g. "Is there a way to remove subproblem X?"), they found it themselves, or sometimes better solutions.
I now make it my goal to understand their problem and its different parts, rather than to solve it, and this allows they themselves to generate the best solutions.