Be explicit about what forms of (re)distribution are allowed instead of going for a blanket license. Where appropriate, also be explicit about what is not allowed.
It shouldn't say much more than "you give us the right to use your content to fulfill the services you ask us to provide, and you have the right to remove your content at any time."
It shouldn't say much more than "you give us the right to use your content to fulfill the services you ask us to provide, and you have the right to remove your content at any time."