Upgrade suggestions sought

I recently bought the B&K Ref 50 preamp and now have the upgrade bug! Currently use system for 70% HT and 30% music.

Current System:
Speakers--All NHT: 2.5 in front; AC 1 center and NHT rears.
Amps: Acurus A250 (front) ; and 200w x 3 way for center and rears.
Speakers and Amps bought around 1997
Sub: Earthquake Supernova 10in. (just got this 3 months ago)..
Trying to figure out what to upgrade next-speakers or amps and where I can get the best bang for the buck. Appreciate all suggestions in advance.
I use a Parasound amp and processor in my home theater system and I just replaced all my cabling with Signal Cables. I found this replacement to be the "biggest bang for the buck". Best of all it did not break "my bank" and I was able to purchase some music DVDs with the money I saved. Good luck!
Get rid of those acurus amps. I auditioned them about 5 years ago and thought they were some of the worse sounding (brittle, bright) amps that I had ever heard. Could not understand this because their intergrated amp (DIA100?) sounded pretty good for the money.
Superfly, I had the NHT 2.5's a few years ago. Also in an HT type setup. They are nice speakers in many ways, but I found myslef listing to the speakers rather than enjoying the music.
I bought a pair of Von Schweikert VR3's and that was a huge improvement. Music was more, well, relaxed and enjoyable. Less glare. For the HT side, they have deeper bass than the 2.5's so I think you will enjoy them in that regard as well.
The VR3's got me going full bore into audio. Soon after, I dumped the HT.

You can find these for under $1k, and if you really like them you can send them to Albert for a total overhaul.
I went from the 3's to the 4's, and last year I had the 4's rebuilt.

Settle you speakers first, then look to other component changes.