I may leave out the inverse kinematics, as I want to have full control over the pose of the stick man. I may make a seperate version with the inverse kinematics too.
Instead of a seperate version you can try to create a toggle between IK and FK (Forward Kinematics) like you have now. This is common for animation software as FK is usefull for mechanical parts, while IK is usefull for natural motion.
I'm quite familiar with IK/FK because I used it a lot for 3d animation and I'd really recommend trying IK before animating him with FK, you'll thank me for it eventually. We're usually only interested in where the hand/foot should go and the rest of the limbs automatically adjust themselves to make it so, we don't (like with FK), first move our upper arm, then lower arm and finally the hand, it all happens in one smooth motion. This is exactly what IK does.
If you need any help on implementation I'd be happy to help, as I skimmed through a chapter on it in my favourite AS book. I also have a lot of possibly useful tips from my 3d animation experience.
Anyhoo, I think it's a really cool project (especially in js), keep it up!
[EDIT] Ah, for static posing FK is fine, but some animations would be really awesome!
