For avatar making, what are the limitations of VRoid, and is it just better overall to skip it and do everything in Blender?

Secondly, is it better to stick a Leapmotion to a Vive Cosmos to track fingers, or just stick entirely with a Rift S?

Lastly, how often and acceptable is it for people to use open licensed model components (like hands, etc) to speed up modelling and commissions?