How about thumbs up and thumbs down buttons in the lower right corner of each post? Only visible to forum members, and once one of the two is pressed, they are replaced with a score showing total number of thumbs ups/downs (visible to guests also). Just have a +X(in green) or -X(in red) shown. (Like some other forums have) Ofc this should probably have total anonymity.
AND/OR have one of these somewhere beside each tower/item submission, so that users can quickly state their opinion on certain towers. (Ofc this one would need an option for user to change their mind once they cast their vote, in case the tower is updated to change their opinion.) It'd help in deciding on what should/shouldn't be approved. This could be then expanded to the search, so we can easily filter by 'awaiting approval'; sorted by highest rating.
Just random ideas.