[rat of vengence]

Ok, so with guard you are facing tanks which are tough, and troops which are woosy. You have the bike melta squads to bust tanks, which is good. If the squad with the Attack bike is for anti troop, then give the 2 bikes flamers.

Your assault troops should be anti troop as well. You want to get them into combat and safe from template death. Ensure they have cover saves!
I would use flamers on them instead of plasma since the guard will most likely be in cover. No cover saves to flamers! TOAST! Other than that you won't melt a 27 point marine with an over heat that way. Better still lose the special weapons on the assault squads and give one sergeant Terminator Honours and a power fist. That squad will be able to take anyone and anything.

RoV