I've been messing with an alloy compound from Precious Metals West..
I use 50% 18K Yellow & 50% 18K Red (I think they call it "Russian Red"
It comes out with the most beautiful , gentle red, distinct from anything else I've used (tried the same in 14 K, Same result but maybe a bit redder..).
Fabricates easy, no cracks, no deep oxides. It also doesn't do the rose gold "Slump" if too much heat is applied.
It may not be your solution but It's worked well for me.