Hmmm those Baals are a bit fudged up. See, with Baal flamestorms you will be going forward as fast as you can. This means 18" and popping smoke. Next turn you will move up and burn (probably move 12") and next turn you're dead. This is the nature of the flamestorm Baal. I would make these cost as less as possible if you're dead set on taking them. Personally I wouldn't take them in either form.
Stormraven, you need two of these for armour and target saturation. I would take the lascannon and multi melta as they are free and the multi melta will be handy as you're up close anyway.
Assault Squads, how many dudes in each unit? Seems like wrong wargear in these units. Should be dual flamers and power weapon/claw or dual meltaguns and power fist/hammer.
No point in the Techmarine. He cannot keep up with those fast vehicles and he's not a I.C to join units inside the Stormraven.
Reclusiarch is cool, Librarian is better as does the same trick but better.
Captain is just plain rubbish. I would really drop the Captian.
Hope that helps