Question if better option would be limit by armor type?
Image XFiles where you have submarine and only armors for underwater are allowed.
Or car where you can't fit power armor.
@Delian
Unique new tag have benefits, it make easier to maintain Cartesian cross of all crafts and solders/armors.
With simple list of types when you add new solder you need visit all crafts to update one where it could use it.
With new tag you only copy paste config from other unit.
I think it could be implemented similarly to base functions where you can create new types on the fly.