Just an idea.

Alternatively the community could just report spammers and leechers and the team can ban them. This saves having to waste more server resources by implementing new stuff to try prevent spam. There will always be some sort of bypass found by someone. I hate seeing spam as much as the next person and report spammers/leechers from their profile daily and it's annoying but when it's done it's done. If you hate it that much you can adjust what you see in the Activity Feed here. I am personally against adding more to the to-do list for Aoki and Sozin especially when it's something that gets dealt with pretty swiftly usually. There is a staff member online pretty much all the time to deal with the threads when they've been reported.