We are limited to 9 (or 10?) bases, that sharply limits your upward bound on production/credits. I haven't seen any 3 crystal asteroids (I assume it's only moons), and land area is only something like 65. That ain't much to work with.
I see the argument for taking a good moon - high fertility, metal, and crystal, with decent energy. It's cheaper to defend with shields, and it's only 10-15 smaller than a planet. But an asteroid? Hell, if my starting base were an asteroid I'd already be getting nervously close to full.