High Rez audio over HDMI


I have sollicated input on this issue before and appreciate all perspectives. Based on what I have read and heared myself, High Rez multi channel audio over HDMI is far from at its full potential and to some people (including myself) MC analog well done sounds superior. However, the Meridan HD621/861 combo seems to take it to the next level, albeit at exorbitant cost. Then there is the long awaited Theta CB III + HDMI due to be released, which one might hope outperforms their analog six shooter setup. My question is this; what is my best strategy in terms of optimizing bang for the buck and timing of upgrade to take my multi channel audio system to the next level (I am currently using an Onkyo 885, using SACD over HDMI and Blu Ray analog). I see a few scenarios:

Try to pick up a reasonably prices 861 and buy an HD621 for 3K. Total cost 9 - 10 K. Performance improvement ??? Timing - now

Try to pick up a reasonably prices used Theta CB III and get it HDMI upgraded for 4K. Total cost 8 - 9 K. Performance improvement ??? Timing - hopefully within the next 6 months

Buy another used acclaimed processes (Cary, Halcro, Classee) that supports HDMI. Cost 3 - 6K. Performance improvement ??? Timing - hopefully within the next 6 months

Wait for the technology to mature and someone comes out with reasonable priced gear that gives me Meridan / Theta level performance.

I'm curious about others' perspective on these options, and which path they would choose (or have choosen)
edorr
You don't get to use the single CAT-5 cable but instead use 3 S/PDIF cables (smartlink/MHR) to transmit the digital data from HD621 to G68.

Trifield is great for many recordings, especially good ones, but I find I use the "musiclogic" program a lot. There are a lot of choices. YMMV
In fact, I thought about it. Especially given that a used 861 really can't be had for anything below 7K it appears. Adding in 3K for a HD621 for a 621 puts it out of my leauge. I am using a Sony XA5400 ES for SACD/CD and a Pioneer BDP 09 FD Blu Ray player for sources. Just wondering if I bought a G68, would it be upgradable to support the MMHR interface coming out of the HD621 and if so at what cost? One very desirable advantage of this path is it would get me the trifield option.
Have you considered a G68 which you can buy in the lower tier of your ranges? Pared with an HD621 it sounds pretty nice. What source are you planning to use?