The only downside to this is that you can almost guarantee that if the Announcement board becomes "pay to post a new topic", they will just start spamming their new topics in every other board instead. Obviously these threads will get trashed, but since we have so few moderators, the threads will likely be up for several hours and be spammed to high heaven before they are.

I like the idea of the owner having a "bump" button, and therefore completely eliminating paid bumping by any means. As an add on to this, I would suggest that each user can only bump a maximum of 1/3/5/whatever-number-you-like thread(s) they own per 24 hours, to stop the creation and bumping of mass dummy threads. Might be worth having a caveat that the owner has to at least be a member or have at least 10 earned merit or something similar to stop newbies from creating mass threads.