For what it's worth, I agree with you on almost all of that. I think the main difference here is that I see the labor theory of value as being much more fundamental to Marxism than just, as you put it, one facet of it. It's very difficult to keep Marxism as a whole if you toss out the LToV, since the whole structure would begin to crumble. It may be possible for similar models to be put in its place to prevent the crumble, but I think that those models would have to be close enough to the LToV that the distinctions wouldn't really matter except to academics. (edit, fixed a word)