mmh...honestly i think you will be doing good in friendly games. However, what i learned using IA13:
-NEVER spend too much on the command squad. they just die and have a big target painted on them. Thats it. My command squad is 65-75 pts.
-Big blobs are good and funny, but even if you never run away, they just die. so, either you horde big, or you ought better have a plan
-Tanks. dear god. tanks. nothing unsettle the opponent like 3 undercosted demolishers escorted by 3 hellhounds running at him. otherwise Wyverns. 6 of them. say hello.
usually the plan is : small HQ, nasty fucking big horde, an irritating number of artillery or ordnance tanks.
I also found out that under 2000 pts, bringing a baneblade is the certain recipe for getting beaten AFTER the game.
Anyway, about the order: you just ordered what you need for basis. Then you'll need another 2 platoons and some artillery pieces and tanks. say 3 wyvern and 3 demolishers. there you go. base list ready.
Then, if you want to be a punk, take 3 arvus lighter and jump around with your 3 units of melta toting marauders