First off, thank you all for the feedback and support.
I also do not see a reason to change them. And do not like the chains. I have never seen a throwing weapon anywhere that has chains on it like that and I don't see why they would be put on. What benefit would they give to counter act the weight of them?
The main reason for me to add something like the chains was cosmetic means only. There is no real use for them, but it makes them look more "complete" from my point of view. I'm trying not to be making another stick with a tip at front, I'd prefer having something more than that, not saying the others were worse in any way. Besides that I think it is worth a try, depending on how it is going to turn out afterwards. taking a look at the chains themselves, I think I'll have to rework them either way, they don't look twisted anymore but just all over the place.
The head of your Rupturers is very beautiful, at least to me. The problem with it, however, is that it is very large: the head itself takes up 1/2 of the whole weapon, and the blades of the head are very, very thick. The weapon's head being this large would also make it ineffective in real life, as to throw a weapon of that size you'd need some insane arm muscles or a ballista (and that might not even be enough). For a head this large, you would also need a very large counterweight - I don't even know how big the counterweight would have to be, but if you plan on sticking with your current head size, you'd have to make your javelin look like a maul at the end. All in all, a quick fix, just use either the current Rupturers model or other javelin models as an example for what a good javelin-head size is, resize, and you should be good to go.
I don't really know what to say about the chains. Sargent Q's post is right; there really isn't any other javelin that has chains on it. While he may not like the chains, I think that makes your model unique and I'd love to see it done correctly if you manage to do it. I don't have any good examples for you, so good luck, I guess.
I'd be really interested on what colors you plan on giving your Rupturers! I feel like the right colors could make this weapon look even more badass.
I'm most likely going to have to scale the head into proper proportions compared to other throwables, though I would like to keep ot comparably big (not too big though). I've already adjusted the thickness of the blade, so it's actually looking a little better (and lighter).
As I already said in response to Q's feedback, the chains will be reworked to a lighter (thinner) version, perhaps I will add some strings for tying the teeth to the stick.
As for the colour scheme I had in mind to make the stick a dark brown and rather smooth bark, the teeth would be somewhat beige, having dark red and green accents all over the spear (eg. red strings, green bandage around the grip). Over all I think it should be dark-ish since that fits weapons themed old and primitive better thank any other bright colour.
The stick itself could use to be a little more bent and less straight as I would say,
just take a look for yourself (p3d.in).