I think I'm with the majority of responders on this one: Give the bird the bird.
It's beer, man. IMHO, the branding and advertising is too cerebral.
Like Denny said: "I've never heard of a yellowhammer. For that reason, I prefer the logos that have a bird representation on them to give me an idea of what the hell you're talking about!"
Now, a big golden THOR hammer on a tap handle--EVERYONE will want to know what that is all about.
But like Glitterbug said: "The label sells the first pint. The beer sells the rest."
And, when your brewery takes off and has more than one beer to offer, label the hammerhead and/or handle.
I've no skin in the game, but I'd reconsider all 5 -- they're too busy. Just being honest.