Omeka S for crowdsourcing (add new items)

Hello,

what are the options for a crowdsourcing project which aims at making it possible for members of the public to add new items?

I know of the Collecting module, which is great, although it doesn’t offer much in terms of user authentication. For a project like this I’d like to enforce of course some checks, e.g. the user needs to be registered as a guest or something like that so that the email is validated and we know who is submitting what.