I think this is dead on and the only thing I would add is if they are wanting to use your web app, and thus be a user, I would treat them like every other user

I think this is dead on and the only thing I would add is if they are wanting to use your web app, and thus be a user, I would treat them like every other user you have. It doesn't mean they will get exactly the same interface, but your view of them should be the same.