What about a Gryphon DAC since you have a Diablo?
I would also look into Aavik DACs. The DAC in my Axxess (Aavik’s budget brand) Forte integrated is absurdly good for being a built-in unit in a $5500 integrated.
If a Holo May was merely “different,” I suspect you might end up chasing your tail in trying to upgrade the Directstream.