It would be good to have the option of disabling comments on Dreamwidth but allowing them on the crossposted entry (and preferably on a post-by-post basis, though I can see the danger of options-creep there). Right now that's only possible by editing the remote post. I wouldn't use that functionality myself, but I know a lot of people post here because the DW crossposter is so cool, but still prefer LJ as their main 'home'.

But I don't see a good reason to make that the default behaviour. I prefer the default to be comments allowed everywhere, with the option to disallow one or the other.

True, in heavy metadiscussion it's way more convenient to have comments all in one place but that's not what the majority of posts are about. The default should always be what works best for the majority of posts.