Let's see, I've got a bit of time to break this down best I know how...
Space Marine Captain
Vulkan He'stan
Pred And Vindicator (Maybe 2 Predators)
Assault Terminatours in a Land Raider Redeemer
Ven Dreadnought Assault Cannon
Attack Bike Squad
2 Ten man Tac Squads with meltas in Rhinos
With what you have listed already, I'm calculating at least 1500-1700 points.
Vulkan lives with the Assault Terminators, and their Land Raider can move up, providing cover to following Rhinos.
The Vindicators and Ven Dread w/ ass. cannon can sit mid-field.
Predator sits in a corner.
The Attack bike squad lends support wherever needed.
I like Bikers, but I think there's a great argument for Scouts + something else with the points saved. The Scouts can hold an objective in the backfield and shoot at things. I figure with a small Scout squad you could squeeze in a second cheap Predator.
If you choose the bikers, at least consider giving them flamers. You have little in the way of anti-horde. If you load the bikers up with meltas, expect them to be targeted.
If decide to put the Ven Dread in a Drop Pod, then what Benshin said.