Mikey, I'm in the middle of moving so I won't have the opportunity to try the GTX-D Gold. I have lot's of experience with Furutech power connectors and IEC inlets. Their gold products are very warm in sound (FI-11, FI-10). I can't imagine the GTX doing any harm, not even the Rhodium.
I haven't tried the Golden Cross. If you aren't seeking to attain Cardas Clear levels of resolution, I would fully recommend trying Purist Audio Venustas (Praesto) cables (IC, SC, not the power cable). I replaced my Cardas GR speaker cables with the Venustas. It took away the sibilance that the GR had and produced a 3D like soundstage. Imaging was far better and more realistic. Bass and mid-range bloom remain, but the highs are much more clear. It is very much as warm and full as the GR. However since it is a laid back/relaxed sound the highs do no harm. Overall, the Venustas will give you more of what you like of the GR with less of what you don't like. I don't believe however, that it is at the same level as the Clear in terms of timbre, clarity and resolution. You could rent (borrow) from the CableCo. If you like it, I highly recommend the Purist dealers on Audiogon (I've bought from three different dealers here). Message them for up to date pricing and I think you'll be surprised on how good of a value the Venustas is. Purist also has another cable called Aqueous Aureus. It is smoother than the GR, perhaps even warmer. Highs are slightly more liquid than GR too. The speaker cable has strong bass (after 150 hours break-in). But overall, I think it's in the same general class as the GR but more refined (it is also cheaper). The Venustas is a big upgrade.
Since you like the Golden Cross I suspect you may have a little harshness in your system? A friend of mine let me borrow Black Diamond Racing cones (BDR) because I had this issue. I found BDR MK3 Cones with BDR MK4 pucks on top are amazing upgrades if you have no isolation. A lot of the harshness i had was because of not having any isolation. The cone/puck combo improved every area, no weaknesses. You'll find more bold images, improved bass, expanded soundstage and smoother highs. Other isolation products I found to be here and there with improvements, but the BDR's just seem to work.
I would also recommend taking up the Akiko Audio Tuning stick trial offer. To smooth your system in a warm way, try the AC stick. To add clarity and dynamics try the RCA stick. Or try both and return the one that doesn't work. This little sticks can make more difference than cable changes!