ReserveCop,
The answer depends on your tactical application - sniper/observer, primary duty rifle, SWAT/SRT/CQB, etc.
For a sniper/observer (other than .308) I would personally go with a 24" bull barreled rifle (DPMS or Bushy), 1/8 twist with shaved or rail type gas block, free floated, pure flattop or raised rail, scoped 10X with mil dots, equipped with bi-pod, Jewell two stage trigger and aftermarket pistolgrip that repositions the hand farther to the rear. This setup will run $800-900 for the rifle and another $300-500 for the scope and $200 for the trigger if needed.
For a primary duty rifle I would go with a straight A2 rifle from Colt or Bushmaster with a 20" barrel in 1/9 twist. Ought to be able to get one for $750-900 (post-ban) depending on brand.
For a CQB gun I would go with a Flattop 16" HBAR with shorty handguards (Colt or Bushy). I would add an optical sight with iron backup, a light and a tactical sling. If it was a pre-ban I would also get a 4 position collapsable buttstock. Basic post-ban gun will be $750-850 plus $250 or so for the optical sight, $25 for the sling, $150-250 and up for the light. (I have a nearly new post ban of this type for sale because I recently obtained a pre-ban that replaces it - e-mail me if you are interested.)
These are my actual choices for the applications listed - your results may vary.
Mikey