Now, this is likely already been suggested, i've actually know where the hooks can be placed for this. not being a forge developer, it's best to just put it here for devs to read whenever.

 

1: Custom render passes.

  Within RenderLiving; there's an area where it calls multiple render passes, right now it's set to 4, adding a getRenderPassCount() integer there would give modders the ability to add their own level of detail without adding their own classes.

 

2: Custom Armour render

  By using the first method, there could be a system for armour rendering. Each piece would have a getRenderPasses(), and the getRenderPassCount() will add all these together, on rendering them, it will pass to the Item itself and call the method(by counting it's own render passes from 0), an interface containing a pass count and render script would mean each item would have it's own level of layers, colours, etc.

 

3: Weapon reach support

As this is suggested to weapon modders frequenty; it's not actually supported. and means of extending reach is real buggy and has issues. while decreasing is impossible. within (not sure anymore where it was) there was a script to get the players range (in creative, it's larger if not, about 4), adding a getReach() in item can be passed through this to allow flawless weapon reach support

 

*just chucking this out here, you may have already considered these methods.

All three of those can be done with the functionality you're already given.

that's with transformers isn't it,

No, basic java mechanics.

well a lot of methods do cause problems elsewhere, is there a particular way that would yield a result as well as a hook would

I don't have code off hand, but everything that you've described has been done before in various mods {before you ask no I dont have names cuz im bad with names} without base edits.

I would advise going at each part one at a time and looking into all of the related code to see where you can slide in using the mechanics that are built into Minecraft already.

right now, i've done the weapon reach with tick handlers, but it only works on lengthening but hits entities when interacting swings(like doors)

 

anyway, this is off topic and would be better off moved to another section