Papertrail--yes, the power cord upgrade helped my player. It produced more extension, energy and definition in the bass and more detail overall. (If I'm not mistaken, this is the kind of improvement everyone notices when they upgrade power cords from stock, no matter what the unit is--source or preamp.)
About detail: my small experience leads me to distinguish real from apparent detail. The latter is a kind of artificial brightness, the sort of thing that can be exaggerated by less-than-first-class electronics into midrange opacity and high frequency aggressiveness. Real detail is additional information; perhaps micro-information is a good word. It lets me hear more of things like instrumental timbres--the rosin on the bowstring, the woodiness of a clarinet--and the dimensions of the recording space.
As for the amp suggestion, what I mean is you could swap your current HK receiver for any other unit you could get, 2 or 5-channel, just as a tryout. Not a sidegrade, though. Try something which would definitely be a step up. As an alternative, you could take your player and interconnect--or your receiver--to an audio pal's place, or a dealer's, to try it in another system. The objective would be to isolate what's causing the edge you hear.
On Dave's point, I think he is right about room and power line treatment, but most of us seem to want to get the major system components that satisfy us first, and then go into those domains. Not that you couldn't start exploring now, perhaps with an isolation transformer for the player and corner and wall junction absorbers. However this would multiply the number of variables you have to deal with, and I'm for solving a problem one step at a time. I suggest you try to eliminate the amplification as a problem source before you consider changing speakers, for example.
If you do come to speakers, though, after you eliminate both the receiver and speaker placement as the issue, then I second Paradigm (Pabelson's point). Their tonal balance seems less forward to me than PSB or NHT.
