1. Cool bike.
2. The fit looks fine to me. If it feels good, ride it.
3. Disc brakes are notoriously finicky. Just wait until you have your first biff and you bend the rotor a bit. Make sure Larry is nearby.
4. Are all rotors on 29ers 185mm these days? I thought they used the larger circumference rotors only for downhill bikes, but I know little about 29ers.
5. Have you ridden the "standard" MTB before? I'd be interested to hear about which one you like better.