Thankfully, I'm happy with Leech's head. The sheer horror behind the concept of Leech works for me.
He's got this mouth full of huge teeth he's going to clamp down on you with, so he can suck your blood/lifeforce/energy.
He's like a B-movie monster to me. It may seem contradictory, but I just can't get past Clawful's stupid eyebrows. That's a feature that just doesn't belong on Clawful. He literally looks like a muppet. At least with Leech, he has no offending features like that. Buzz-Off just looks stupid.
Leech still looks like he'll eff' you up with all those teeth.
I love him.