Simple User Generated Content

I’ve been researching various plugins to enable a very user-generated content site, but most of them seem to do more than what we’re looking to do. We don’t want a social networking solution (BuddyPress). We just want visitors to be able to:

1) Register for membership entirely on the front-end
2) Collect additional member profile data (Register Plus plugin)
3) Submit comments held for moderation (or submit posts and hold for moderation)

Any suggestions?

Thanks!