as my own personal concept thread i can ramble on a bit here.
the concept for this mesh is a Dragon, its being based on a serpentine type rather than the traditional lizard dragon model.
so heres some things i need to consider during the concept stage.
the head mass ratio to the neck as Thomas already said, the head needs to be fairly small, the neck cannot be too thin or too long but needs to be fairly narrow for form, same for the tail.
the body needs to be pretty compact , thats where all the power ie muscle is.
shorter spine/ less stress, the tail is the rudder so can be much longer than the neck
rear legs need to be pretty powerful as they need to be able to launch this creature.
i dont believe in four legged dragons as such, the wings ,same as a bat or bird would have evovled from the front limbs, that makes sense
so no four legs.
end of ramble, ill post some more concepts shortly.
stu