Hello, 
I do not know if it's possible to make a suggestion or if there is a place for that kind of topics, but here goes:

When exporting to Unity in my case I need to have the Morph slider for Mouth Opening.
If we use InstaLOD it's not possible anymore to use it, which doesn't make any sense in those two cases:

1- Exporting with Remesher and keeping the original avatar for LOD 0
As the original avatar has all blendshapes, it make sense to have the mouth open shape here as well

2-Exporting with Merge Material option
It's a no brainer in that case as it's the original avatar with only textures merged. I don't see any impact on blendshapes

Could the dev team behind InstaLOD consider this please?