Going to a Tournament on Sunday, this is what I'm thinking on running at 1250pts.
Iron Warriors Combined Arms Detachment
Daemonprince of Tzeentch, Wings, ML3, Spell Familiar, Fleshmetal Exoskeleton
x6 squads of 1 obliterator
x3 terminators with combi-plas and lighting claws
x2 meltaguns, lighting claw
x5, x1 meltagun, champ with power axe
x5, x1 meltagun, champ with lightning claw
So, lots of firepower. Prince will take Psychic Shriek, and will probably roll his other two powers on tzeentch (hoping for Baleful Devoltion, and/or treason). Terminators deepstrike. Oblit's can deepstrike too (maybe a couple to try and drop on objectives. I can potentially (based on my opponent) deploy just the prince, who flies T1, and then keep everything else in reserve. The Prince with a 2+ re-rollable armor save, and 6+ FNP should hopefully be hard to deal with.
Not sold on the Havocs, but they are more bodies and the Rhino's I want to protect the Prince with in case I need to null deploy against Genestealer Cults, or Drop Pods.
I just love having obliterators as troops
I have a helbrute and a vindicator I can also bring in, but I don't think they are any more useful then what's already in the list.