One post per hour is too stringent. I mean, the Politics thread would be way less lively if that were the case.
I mean for new members. Lots of forums essentially have tiers, with the new member tiers having limited abilities. You can ask a question with your one post per [time limit], but you can’t spam. Once you reach a certain duration as a member, or post count, your limits can be reduced.
It doesn’t prevent spammers from existing, but it slows them down. It makes it so they have to spend a week or more building up an account just for their several minutes of being a dick-face. Making admin-approved account creation will hopefully prevent them from just starting (and maintaining) 12 of them at once to build up an array of accounts.
Yeah, new member restrictions makes sense to me. Things like no images or links before X amount of posts, that kind of thing.