"(2) the permission to destroy the originals (you'll always find a few volunteers)" why? So, the send a copy of me, so what? It's Geekoid2. It's not going to come back and claim my social security benefits.
Of course; if we can build people, we would build more optimized people and not copies. Skin color, hair growth, strength, spectrum off vision would all be customized to the unique properties of that planet.
So your proposal is that we build a genetically-engineered race of super men? And then send them off into space in deep freeze so they can return some day and conquer us? What ever will we call the ship? I think S.S. Botany Bay is already taken, but let me check up on that.