Make a list of "reserved" labels and prevent users from using them in the request system.

[Tomoyapl]

There should be a group of reserved labels that shouldn't be possible to add as an extra link, such as:
csdb, sceneorg, scene.org, demozoo, download, also all variations of "download" (redirect to "replace main download"?)
In case user tries to add such label, redirect them to the "fix me beautifull" thread (post whole request there automatically?)

[sagamusix]

Or even better, make adding csdb/demozoo/etc. links easier to add through the request system as well.

[Tomoyapl]

I agree with Saga. More and more users are trying to add demozoo links as "extra links" (and I cannot blame them).

[sagamusix]

Demozoo's way of doing things (just recognize links of specific type and treat the appropriately, e.g. turn ModLand "extra" links automatically into download links) might be helpful here.