To me, this is just asking for more intense feuds. Neg rep, in total, will likely decline, as many people will refrain due to lack of anonymity. The proverbial "neg rep pussies" will disappear, but we're just going to create a new problem.
With public rep, I expect that the majority of neg rep will be returned (i.e Poster A negs Poster B for a certain post, then Poster B searches for a post from Poster A to negrep to return the favor). This is setting up for back-and-forth rep battles, which won't be good for anyone. Neg rep pussies will simply be replaced by neg rep retaliators.
If 2 posters start going back-and-forth at each other in rep, it will likely carry over to threads, eventually.
I strongly disagree with your second point. I fully expect most neg rep to be returned.