I don't instinctively like downvotes either, and I suspect it's mostly my personality that magnifies everything negative out of proportion i.e. there's depressive bias. However, if I get downvoted for something really stupid, I find the punishment a very useful deterrent that also works for my personal life. It's the inexplicable votes that bug me the most, but hey, you can't please everyone.

I subscribed to Eliezer's fb feed about a month ago and I'm glad he doesn't post such unpolished ideas here. I think he also posts there because the commenters are better selected and not anonymous. I might be in favor of an upvote only system, if it weren't for the really terrible outlier posters who need to be hidden quickly. For upvotes only , we would need a completely different visibility system.