I think itd be sweet if we could get command blocks on the creative server. Obviously you could restrict the commands to only work on your plot. I think this would be cool, like you could make a teleporter or summon a giant zombie.
But there could be bad sides.
It could lead to griefing, like /summon, /setblock, and more. Solution: Maybe you could only allow command blocks to be set up by plot owners.
Bottom line:
I believe it could be an awesome advantage for building and redstone and more, but we could all see how it could lead to potential griefs.