I've done some looking around.
For the Wights, I'm pretty sure I'm going with the Neomics "Wraiths":

Which is great, because I like those figures (and kind of dislike the rest of the team. Sorry Neomics!).
For the ghouls, I think I'm going to end up going with Willy:
Those ghouls have everything I'm looking for - they look fast and vicious, everyone who sees them will know that they're ghouls, and they have a lot of exposed skin to make the skull paint really look good.
The only issue is that I've seen these minis before (a friend of mine bought the Willy Undead set) and they come in like three pieces each. And the pieces don't really fit well together. Lots of cursing, lots of green stuff, lots of glue on my fingers before these will be finished. But that's a one-time problem and these guys really do look great when they're glued together.
So now I'm just looking for zombies and a few skeletons!
Plan B for zombies is just seeing if my local game store still has a boxed set of Warhammer zombies. Those come with a lot of spare parts, so I'll be able to mix and match as needed. Plus, weapon snips are a lot easier on plastic models than pewter. But there's still a lot of stuff out there. At some point I'll have to look through Reaper's encyclopedia-length catalog ...