This is my draft list for the AM edition of Adepticon's 1000 point tournament. My goal with the army is to design it sit back and shoot until the enemy gets close enough that I am forced to engage in close combat. I am avoiding hobgoblins (too many models) or K'daai (no models and too difficult for me to convert), but cannot settle on which warmachines to include to the army. Once I deduct for the Infernal Guard and Daemonsmith (which are set choices for me), I am left with ~467 points.
Daemonsmith Sorcerer (general) w/ dispel scroll [Lore of Metal] - 120 points
Infernal Castellan w/ Standard Bearer - 130 points
Infernal Guard (18) w/ full cmd, Banner of Swiftness & Fireglaives - 413 points
Magma Cannon w/ Hellbound - 170 points
Death Shrieker Rockets w/ Hellbound - 125 points
When it comes to other choices, the Hellcannon and Dreadquake are both >200 points, but could add a huge punch to the army. Hellbound makes the warmachine's attacks magical and increases the number of wounds on the artillery, but it also suffers d3 wounds for each misfire.