Just to update everyone.
The upgrade to the B&W 804S and HTM4S are not going to work out.
Kitchen remodeling went over-budget, and taking 2 Disney Cruises (next week and in May), so my funds are smaller than they were a few months back.

However, the new 600-series did come out over the summer.
I'm now planing on replacing my 10-year-old 603 with the new 683, and the CC6S2 center with the HTM61.

Total cost for the 3 speakers is $2000, as to the 804S/HTM4S costing $5400 (MSRP).

I'm going to the dealer to listen to the 683 some this week, but they should sound better than what I have, since they have the Natulius tweeter and FST midranger.

I did replace my MIT T2 BiWire cables this summer with MIT Shotgun MH750 BiWire. That alone made a noticable improvement in the sound quality when used with my 603 speakers.