My pleasure to comment! If you get a chance to try one, based on your preferences, you may really enjoy the Analysis Plus Solo Crystal Oval interconnects. They're about $250 or so used for a 1m pair.
The Hero is a very timbrally pleasant sounding cable, but I think it attenuates high-frequency detail to some degree, and bass can be a little round when compared to dead neutral. This can make them sound on the "soft" side, and this makes them a very popular choice as a non-harsh sounding cable. For the pleasantness of the cure, however, some detail may be sacrificed.
The Analysis Plus should be a little tighter in bass, a little more neutral overall, and give more high-freq. detail without going so far as to sound shrill. I've definitely got a system (horns) where I notice "harsh" very quickly, and found the Analysis Plus to be just the right amount of detail without the harshness.
So along with the DAC (which would be a big upgrade, and the Bel Canto sounds like a good fit for your preferences), experimenting further with the interconnects could also yield some incremental improvements toward the sound you're looking for. At any rate, it doesn't cost much to try (as long as you don't step all the way onto the merry-go-round!)
