If you plan on possibly breeding one day I'd recommend getting a female, that way if you decided to bred down the road you've already got older girls, then you'd just need to pick up a guy who can be ready in as little a 6 months from birth.
But if you plan on keeping only 2 Ball Pythons, and one them being a morph I'd have to recommend a few of my favorites co-doms:
The Mojave (left), The Black Pewter (crawling to the left), The Killer Bee (bottom middle), The Super Pastel (top middle), The Lesser (bottom right), and The Black Pastel (right)