no problem. Looks like you have a lot of stuff to play around with (btw loving the name and the theme for the army) and you should be able to make competitive lists with this.
to narrow it down a bit more:
What style of army are you going for? CC, gunline, hybrid, mech, footslogging or a bit of all of these?
Are you planning to start out with lower point games? I would recommend this as it would help you get a feel for each of the units as well as their strengths and weaknesses. Tactica articles help with this but IMO, its best to try it out firsthand and see what works for you.
You are right, possesed should be ignored completely if you want a good army. The plague marines you have are great for holding objectives and are a real pain to move (i know from experience). The zerkers are a very solid CC choice and are scoring to boot! keep in mind however that they die to shooting as easily as normal marines. I would try and get these guys in CC as soon as you can and give the sergeant a powerfist to stop your unit from getting tarpitted by walkers. I dont have much experience with CSM termies, but they should do well in the land raider and with the lord.
Eldar are quite annoying because they dart around the board quickly and use their high initiative to hit you before you can hit back. To fight them on your terms i would recommend a DP or sorcerer with lash of submission so you can mess with their battle plan ( im not sure, but can chaos sorcerers neutralise psychic power like C:SM librarians?). Crack open their vehicles, fight CC on your terms and remember that they might be hard to catch, but once you do, they die swiftly.
Hope this helps and good luck to you and your Iron warriors