Basic L/Russ are quite handy, and come with a goodly amount of range.  I also like basic plasma tanks, for three chances of hitting something, and as my last choice...Hydras, as the amount of high strength shots with re-rolls is great.  2 for 150 points please  
 
 The other thing you can do to help is a Vendetta, as you will definately struggle against AV14 vehicles.
 
 Demolishers are too short ranged, punisher not reliable enough and the Exterminator not enough 
AP.  I don't rate the artillery, as they don't have the survivability of a proper tank.
 
 I load up on meltas in chimeras, and only have a few plasmas to bulk up the shooting.  In my 1500 its 4 melta in the coy 
cmd, 3 more in one vets with shotguns and 3 
plas in vets n lasguns.  I fill out the rest with a russ, 2 executioners, 2 hydras and 3 sentinels.  Supported by a vendettta and 2 chimeras.