I have already answered this question in other post. This feature will not come soon for multiple reasons. Some of them being:

• data storage
• 3D model quality
• copyright

wait, I know! You can use javascript localstorage to allow the creator to see the model, but things using custom models cannot be made public, so no errors occur. This will solve the data storage problem because it will be stored on the user's computer, the model quality problem also because it's stored on the user's computer, and the copyright issue because none of the creations will be public.

I still understand, though, if you don't accept.