It may be worth considering whether your intuitions and priors about how serious a problem trolling is is at odds with the impression of the rest of the community. Or, it may be that most of the people you have attracted here are somewhat more tolerant of some amount of trolling. It seems at least from the general voting in this thread that most of the community is not happy with even this change, let alone the other changes you are suggesting.
Biased sample if those who flee the long-replies-to-downvoted-comments threads have already left. At the point where LW starts being unfun for me to read, I panic. If my standards are too high... well, there's worse things that could happen to a site, like my threshold for alarm being set too low.
Has anyone yet mentioned or reported that for the last couple days, the "karma for last 30 days" is showing zero for everyone? And that we no longer can see the top contributors for the last 30 days either?
Do we have an explanation or estimation for a bugfix on this?