Okay... I think that all of those units, except the Guardians, are waaay too small. Two casualties and they're in trouble, three and they're toast...
Is that seriously 2003 points? There hardly seem to be any models there?
Anyway - back to tactics... Watch out for transport vehicles with the blood angels. Shoot them down to buy some more time - the 18" + disembark movement is a real problem.
Put the Avatar in the middle of a unit to use them to hold your line - probably surround him with scorpions, and position the unit to respond to anything that threatens your guardians.
Shining Spears - use that brightlance well, as you're paying about 100 points for it... charge them into combat only to support another unit, or they'll get minced.
Hawks aren't so useful against Blood Angels, but you can try to pick on smaller units that try to shoot you. If necessary, throw them away in a charge at a Blood Angels squad to prevent them charging you. The exarch ought to have a web of skulls in order to do any real damage to marines.
Use the rangers to target any unit out of a transport that gets too close, but don't expect them to do much. It'll be hard to cause a single casualty, and marines don't often fail pinning tests.
Send the Fire Dragons against tanks if there are targets for them, or send them hunting terminators. The squad is too small to do much on their own, so again, gang up with other units.
Also, I'd ditch the haywire grenades and Burning Fist to add another model to each Elite squad. The fire dragon exarch isn't going to help much - maybe put his points into another unit as well.
