I haven't seen skeletons with spears; I've only seen the seventh-level skeleton with a shield and a saber.
Yes, thank you; I've seen them too, and that's what gave me the idea to use the seventh-level skeletons as a base and upgrade, and the spear thrower as a replacement for the archer. Then, we could make a purely visual replacement for the skeletons.
(I'm currently collecting units from various mods; I hope to create such a mini-mod someday.)