Might check out the Army list section... There are quite a few in there for different point levels... Warp Spiders work well against Assault Marines, as the enemy may never get close, and they can use their assault phase jump on the turn they Deep Strike, very nice!
A wave serpent with some Fire Dragons can run in to bust a tank too, think about putting that Autrach with them. I wouldn't use Pathfinders in this list, as they aren't as mobile and may run into some trouble.
I kinda liked "goobi2's Mega Mech list (currently on page 2 of Army list) with the changes suggested by TKE it is a pretty good list. Just take a look and change what you need to fit your style.