I was reviewing the open feature requests on github and came to the realization that a mechanism to share custom templates amongst the users would be a really nice addition. Something like this just for sandboxie: https://marketplace.visualstudio.com/ so a place for free offerings, but we could devise a policy where authors of popular templates get at least free certs. Not sure about the details, authors of shared templates would need some sort of an account... What do you think?
For me it wouldn't matter as long as there is no easy way to abuse templates for nefarious purposes. I have only basic needs for sandboxie: separate sandboxes for forced programs that auto delete after use
If you approve of them first. Then maybe end-users could select of their choosing and add them on the Sandboxie site. I would not be comfortable with other 3rd party methods but maybe it's a little soon for an opinion.