aside from pedro, there are no fists in my army, and im considering removing the power weapon to make room for 2 land speeder typhoons. I can see you point with the 3rd tactical squad, but i have tried that several times, and (this is probably down to my play style) I find that 3 tacticals become rather unwieldy. This list already has 5 scoring units, but maybe a potential 7 scoring units will be useful, playtesting will give me an answer. Don't ignore the humble combat squad, as many of my oppenents have learnt. They have taken down everything from gretchin to daemon princes in cc, I find that a charge from even 5 normal marines and 5 bolt pistol shots can do a fair bit of damage, especially if they strike first. In my last game, my combat squads shut down the rush of chaos marines who had MoS and +1strength from fabius bile, and i was receiving the charge.
I like the ironclad, but 20 points for 2 missiles is a bit much, and in my last game i tried it. I rolled two 2's -.-, and the vindis can hurt MEG, as well as the ironclad in cc (actually he can hurt just about anything).
I am actually considering utilising my assault marine idea, but with vanguard veterans (no, i have not yet gone insane, but im getting there) with jump packs hiding behind the advancing razors to pre-emptively assault anything that looks nasty. if i gave them the sternguard's powersword that would be 8 no save attacks on the charge, along with 12 normal attacks.
thanks for the advice, keep it coming. Also battle plans are welcome, as well as criticisms of my current plan.