Legacy, and that little sense of immortality (but by no means literal immortality). Surely, the clone army is a much greater and more galacticly significant legacy and imortality, but it's not pure. It's created by someone else, for someone else, and changed to be subservient and get old fast... not a Bounty Hunter's dream. A pure clone, however, is even more pure than a natural son could ever be.
He had the oppurtunity, and maybe he wanted something a little different and emotional in his life, more than just the Bounty Hunter's life.
God is a placebo with nasty side effects.