I’ll have a look at the thread to do with category based moderation. It might be an issue if comments are allowed, but as I understand it I should be able to make it read-only to everyone but the assigned user unless the per-category moderation stuff is brought in.
In any case, comments/replies (which I assume people are looking at for moderation) could be done from people’s own spaces and notified through an @ or even just a link. That shifts the requirement for moderation site wide anyway, to an extent. It’s only an issue for people who want to moderate their own comments, which is admittedly a reasonable thing to want.
Thanks for the steer everyone.