A while ago I wrote a Deathwing / Terminator tactica. It's in the SM articles section.
For HQ, I always suggest a Librarian with fear of the darkness and a drop pod command squad w/ 2 assault cannons. Right away, IG, Tau, and Eldar are toast.\
For ELITES, go with at least a venerable dreadnought w/ TLLC and ML with tank hunters. A S10 Lascannon with a good chance of hitting is excellent for tank hunting.
For TROOPs, an equal mix of 5 man termiantor squads with cyclones and 5 man squads w/ 2 assault cannons and a drop pod is good.
Land Raiders and terminator assault squads should be left out of games under 2,500 pts. YOu are already extremely outnumbered, a Land Raider just gives your opponent less targets to worry about.
I'd go with somethign like this:
HQ
Codicier, stubborn, terminator armour, storm bolter, fear of the darkness, 140 pts
DW command squad x4, 2x assault cannons, drop pod, 250 pts
ELITES
Venerable Dreadnought, TLLC, ML, extra armour, tank hunter, 170 pts
Dreadnought, Plasma cannon, extra armour, 120 pts
Dreadnought, Plasma cannon, extra armour, 120 pts
TROOPS
Deathwing Terminator squad x5, 2x cyclone, tank hunters, 290 pts
Deathwing Terminator squad x5, 2x cyclone, tank hunters, 290 pts
Deathwing Terminator squad x5, 2x assault cannon, drop pod, 295 pts
Deathwing Terminator squad x5, 2x assault cannon, drop pod, 295 pts
ARMY TOTAL: 1970 pts
It doesn't really matter what you spend the extra 30 pts on.
I would like to let people know that when the new DA codex is released, you can mix lightning claws into Termiantor squads, so don't go selling off your assault termies just yet.