To reduce forum spam, I think there should be a cooldown for when you post in the forums that bars you from posting again until the cooldown expires. The cooldowns (that I think would be appropriate), would be:
1 forum post (in existing threads) = 30 second cooldown
1 thread creation = 1-3 hour cooldown
However, I think mods should be able to disable cooldowns for themselves, since obviously mods aren't going to spam the forums (hopefully).
A notification saying "Your Thread Creation Cooldown is up," would also seem like a nice thing to have for this specific feature, but it should also be able to be toggled on and off if a person doesn't wish to receive it.
When trying to post with a cooldown active, a message saying "Your cooldown is active," could also be handy to prevent noobs from saying "oh no help me I can't post every ten seconds," in the B&P forum.
I could be wrong, but I thought this was kind of already a thing.