What would be good practices in setting up Character with multiple swappable parts?

Hi, this is what I am planning at the moment,
There is a Character which is divided into 4parts, Head, Torso, Arms, and Legs
Each Parts can be swap to use different Mesh.
Depending on the Part, the Character might have additional Bones added, as well as extra Animation to that part.
Animation is Mecanim Humanoid retargeting base.



I already figured out how to get this working, but I was wondering if there are better alternatives that I should use.

Below is how I set thing up, Please Comment if you think there is something that I should change

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Things to consider:
Simple Mesh Swap cannot be use, since the Part might have extra Deformer unique to it.

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Actual Practice:
1. Create a really simple Mecanim-retargetable Deformer Set with no Mesh in it.
2. For each Part, Envelope them only to related bones within Mecanim hierarchy and Export them as their own FBX.
3. During Runtime, Use Scripts to Constrain Pos/Rot/Size of Part's deformer to the Base Deformer.
4. If the Part contain extra Animation, use Legacy Animation and control it separately via another Script.



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How would this sound? Any other alternatives?