I like that there are two variants, when the corpse spider one came up I was caught properly off guard.
Also, the noblewoman one has a variant, at least as of the current beta. THAT threw me, and I ended up doing something horribly evil and out of character just to see what happened...
The rewards I really like are the ones where a unit joins you - I've had spearmen, archers and pioneers pop up. Really useful early on when it's slow to build stuff.