On a positive note, it seems he is no longer with GW, according to the internet rumour mill this week.
Now we just need someone to retcon all the atrocities he's added to the 40k fluff.
From what I understand (and setting apart the horrible Daemons of Chaos army book) he was actually a pretty good games designer (Fantasy Battle 8th edition got some solid reviews). It's just the fluff. Oh God, the fluff.
With Draigo I hope they go one of two routes:
1) We'll call this the "optimistic reimagining of the Mass Effect 3 ending" approach: as it turns out all the fluff about Drago and the things he supposedly did were simply the Chaos Gods manipulating his mind as he was caught in stasis in the Warp, the intention being to break him by showing that regardless of how many (implausible) things he achieved, he couldn't ever actually win.
2) The "Wire" option: Draigo, killer of Bloodthirsters (in the Warp), burner of part of Nurgle, demolisher of the Everchanging City, Resister of the Handmaiden's appears from the Warp and saves a company of Grey Knights who were in the midst of a last stand against a horde of Daemons and Cultists. As you'd expect Draigo... the single most powerful entity in the galaxy... handily wins the battle and turns to share one last look with his dear brothers before he's dragged into the warp.
Only to be shot in the head with a las-pistol by the kid son of one of the Cultists he'd just killed. The shot kills him dead. Ashamed by this ignoble ending and worried of what the reaction to the greatest defender of mankind being killed by a child with the equivalent of a potato gun, they expunge Draigo's name from the record and invoke exterminatus on any planet foolish enough to have someone mention his name.
Having shown a keen natural talent the kid goes on to be a Vindicare Assassin, making his name through the assasination of a heretic Ultramarines Librarian who'd written some really bizarre stuff about the Ultramarines being the greatest Space Marines ever and everyone being jealous and/or looking up to them.