The point of paying for a spouse is so they get their own membership. If your spouse travels a lot without you this might be a good deal for them to have.

The club promo towards the end of last year was the best I have seen. I bet they won't do another promo until maybe the end of this year. Your best bet would be to just use the CP discount that you already have available.

I don't have a US Club membership but I have never had a problem bringing in two guests with my AMEX Platinum so I can't imagine a member would have any issues.