Careful now, he's a DK2 player.
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And Hapuga, there's nothing wrong with humanoid (we've all agreed though that the DK2 roster is too boring, too human), but for me the fear is that with too many humanoids eventually the roster still gets a bit samey, as you'd have all the units on a fixed blueprint: 2 legs, 2 arms and most likely 1 head. Now you get a bit of variation with the size, color, posture and amount of hair and horns. Add the occasional tail and you're done. If you have a good amount of units types, they start to look more or less the same. Especially since you've also got the converted heroes mixed in.
With a Dungeon-sim this is a bit more of a problem than with other games because you want an overview of your dungeon so you need to be zoomed out a lot, but you still want your units to have individual personalities. In short, you've got bipeds from a distance.
If you drop the humanoid restriction for a significant portion of the roster it's suddenly much easier to have visually distinct units even when you're zoomed out and a lot is going on.