I think it would be much more beneficial for you to ask for a local moderator. You have several very active members who, if they are ready to accept responsibility, should perhaps apply for local mod positions.
We are going to later ask for a moderator, but the need for other boards (especially other discussion which is meant for off-topic) is imminent. If there is a moderator moderating that board, he will not be able to delete many of the posts which some people see as spam, because many are not spam but belonging to off-topic board. Unless the moderator just want to be harsh. It is worth mentioning that moderators have fast response to the posts that I have been reporting on the board.
Yes, I agree with what you said. I happen to be normally active on the Nigerian local board, and I also suggest that there should be some sub-boards, and after the sub-boards, a moderator should arise. The reason is not far from what you have said; there are most topics that should just be on the off-topic board, but they all just get jam packed on one single board, and if there are any moderators now, I think it's actually going to be a very stressful or confused duty for the moderator, but if there are sub-bards, then it will be easier.
I totally agree with what you both are saying, the sub-board is more important than the moderator, why because without a sub-board the moderator will only have to delete, ban or lock post and not to move to anywhere (but can still move to other boards outside the L.B) so the sub-board is more important than the moderator, we should have the sub-board first before we can be ready to have a moderator, maybe a week or more, before we can get a moderator.