As mentioned above, the CC approach is not to mandate public domain for all data, but it's easy to see where that impression could be obtained; apologies for that.
I actually think the CC attitude is neither one of mandating a single solution, nor one of licencing on your terms. The former means we could eliminate all but one instrument, or at least only recommend one instrument per use case, and the latter means we'd proliferate licences like crazy -- maybe we did a bit of the latter early on, see http://creativecommons.org/retiredlicenses
I think the current and hopefully longstanding CC attitude is that a goal of maximizing the value of the commons requires not just one solution, as use cases do vary, but a small set of them, as a large set facilitates lots of content/data silos, which drastically under-realize the potential of the commons. I hope that this is fairly strongly implied by our recently updated mission statement, featured on our recently updated home page and http://creativecommons.org/about