Spend more money on the amp or the pre-amp?

Update for anyone interested:

Got a Rega Brio-R off Ebay ($430) for the KEFs.  Sounds fantastic.

Got a NAD 7175PE off Audiomart ($170) for the Wharfdales - sounds really great.

Thanks everyone for all the thoughts and ideas - really helped me to sort through things.

Congratulations. Thanks for letting us know what you chose. Fill us in with some details once you've had time to evaluate.

Yes, thanks for the update. Too often we never hear back. You did well.

Wow, those are great prices! How's it all sounding?

Sounds like you did well. However, I still want to make a suggestion with respect to the orginal question: how about the new Yamaha RN803d receiver? It is 2x100 watt rms at 8 Ohm, has digital inputs, Spotify Connect Airplay, networking capability and much more. And it has room equalization capability.