My first choice would be to eliminate the Disney Dining Plan completely but since we know that's not going to happen I think that Signature Dining, if it HAS to be part of the Disney Dining Plan at all, should be 1.5 credits instead of two. That would be more in line with the value of the credits compared to non-Signature places.
But again I would rather see a return to the pre-dining plan era. Or maybe just eliminate the Signature restaurants from the dining plans completely.
Or for yet another idea which still fits into Disney's "packages and plans" way of selling things, have a Signature Dining Plan. I know they kind of have this now with the Premium and Platinum Plans but those also include lots of other stuff like tours, golf, etc. I am talking about only dining, mugs and snacks like the other dining plans. Buying this plan would be the only way to dine at Signature restaurants using a dining plan. Just a thought.