I've worked out a list based on what I've got between the BaC and BoP boxes. Floating this list over on /r/Warhammer30k got me decent feedback.
HQ
Warsmith (Praetor)
-cataphractii Terminator Armour
-Combi-melta
-chainfist
Elites
Contemptor Dreadnought
Troops
Tactical Squad (20 man) [mkIII]
Tactical Squad (20 man) [mkIV]
Tactical Support Squad [mk III]
-5x melta guns
Heavy Support
Tyrant Siege Terminator Squad
Iron Havoc Support Squad [mk IV]
-5x Missile LauncherI've already started work on the Havocs. I'm keeping my eyes open for good deals on Iron Warriors shoulder pads, and I have some rhino hulls to convert over to Heresy Era vehicles.
Iron within!
CJ