"Dakkon":
I think that for your proposed $5K budget, unless you're going to go with someone like either Outlaw, or some used B&K gear, I think that you're not going to be able to get a separate pre/pro and matching power amplifier for $5K and still expect to get speakers to go with it. For your budget, I still happen to think that a receiver makes better sense. Now....... on the other hand, if you're going to spend about $10K or more, then I would think about a pre/pro and power amp then. But for $5K???? I don't see how that is doable.
But if I am spending $5K on a system, here is what I would spend my $5K on.
Speaker System: I would go with Paradigm (if I am going to go "omni directional") or Definitive Technology (if I decide to go "bi polar"). For the "Paradigm" system, I would consider a pair of "Atoms", right along with their matching center channel in the "CC-170", with the "ADP-70's" as surrounds. For a subwoofer, I would look at a "PDR-10" at least. On the other hand, if I want a "bi-polar" system, then I would look at a pair of "SM-450's", with a "C/L/R-1000B" for a center channel, right along with a pair of "BP2X" as surrounds. For a subwoofer (and with a Definitive Technology system, unless your room is exceedingly large, you're only going to need JUST one), I would start out with a "SuperCube II" just to see if this subwoofer will provide all of the "oomph and slam" you're going to ever need. If it does, then that's what I would stay with. If not, then you either go with a second "SuperCube II" later on, or upgrade to a "SuperCube I". Either way, I would figure on spending about $1,500.00 to about $2,500.00 on speakers.
Audio/Video Receiver: For an audio/video receiver, I would look at either Denon, Harman/Kardon, NAD or Onkyo's "Integra" series. Depending on how big your room is, I would go with at least a "Denon AVR-3803" or a "NAD T763", while on the other hand, if this is a smaller room we're dealing with here, then I would go with a "Denon AVR-2803", a "NAD T753" or a "Harman/Kardon AVR-430". Either way, count on spending at around $1,000.00 for a receiver.
When it is all said and done, you would've spent somewhere in the neighborhood of $3K for a system, and you still haven't thought about a DVD Player yet. Perhaps, you're already covered in that department right now. If so, then good for you. You're already ahead in the game. With the money left over from the options I just listed above, you can take that money and buy you a few flicks and take your new system out for a test drive.
Good Luck and Happy Shopping!!!!!!!!!
--Charles--