I've yet to get the trick with Undead, so my army is in planning stages. That said, thinking it through: Cavalry is still king of the battlefield. Chariots are nice, flashy units, but TK cavalry and TK Carrion are cheap and very effective.
TK Cavalry is actually quite nice for its price; not quite as nice as Chaos dogs, but still very nice. In theory, two of them can deal out 18 attacks on a 12cm frontage i.e. on a single hapless infantry unit. All told, these two units cost 10 points more than the single unit of Chariots.
So perhaps 3 cadillacs and 6 cavalry is not so bad to start.