I think a new receiver would help. It will get you HDMI that will greatly simplify things and allow you to listen and enjoy the new lossless sound formats, DTS Master and Dolby True that are found on Blu-rays. Also, I agree with considering the Pioneer Elite SC-61 or 63. The new Class D3 amps found in these units have been very well reviewed and received. I have had four Elites now and have had no problems with any of them. I also find their Advanced MCACC very effective and recommend it. While other room correction solutions are probably just as effective (and I am sure you will hear from their proponents) my vote goes to the Pioneers you are looking at. The rest of your system seems solid and I think you will benefit greatly from the receiver upgrade.
See, no smarta$$ comments here. Good luck and enjoy your upgraded system when done.
Marantz PM15S2 LE, Oppo BDP-103, Simaudio Moon 100D DAC
VPI Traveler V2 with an Ortofon Rondo Blue and Simaudio Moon 110LP, Technics SL-1400 with an Audio Technica AT-14sa and Pro-ject Phono Box S
Dynaudio Focus 260's, Rel T-1 and a Panasonic TC-P54S1.