One thing that would be cool is to gather up the Year 1999 launch info on classes, into year 2000ish. Some classes like necro went through quite a few revisions...
Another thing would be a central repository of old zones...Cazic comes to mine... many others as well. I know cazic has been pretty well re-claimed, but maybe a place on the wiki for Old Zones?
Then of course, old items that were nerfed...
Reworking spells to get back some of the original seat of the pants excitement as well. I think this would require a team effort. In order to really revamp a class, you kinda need to have a real understanding of it. Non clerics would likely say something like " Just make a 1 second casting super heal over time that holds for at least a minute, and only costs like 100 mana hahahah"....but that would suck ass for excitement
be nice as a set up super training wheels to make it booring though!f
As for the team effort on spells... even having good representation of the classes giving initial feedback on various spells to the person actually doing the edits would be good...
Just a few ideas.