Thanks, I'll experiment a bit with this.
And yes pure palladium prints can be exquisite, but more usually they are too brown and heavy for my taste. I've settled on an 85-90% platinum / 10-15% palladium coating with potassium oxalate and potassium dichromate. This gives a beautiful, delicate, warm-black with nice clean highlights and good shadows. I've spent a few years getting this process optimised, and I have no desire to lose it. I use pure palladium mostly for teaching or when I want to smother the shadow details.
The route I have taken is to make negatives that need no contrast agent (I am using a pd to pt ratio of about 3:1 ). Of course this does not help if one has older negatives with varying contrast.
I do occasionally use some older roll film negs that need a contrast bump, so I use pd plus NA2 for those, and get a similar color and feel as my larger prints.
Ian, pop Pd (Ware-Malde or Ziatype) can give you dead neutral or even cold toned prints - you can get warm toned and split toned prints too. See this print for instance, it's a pure Pd Ziatype print. It's a simple process (doesn't need any kind of developer, just a citric acid first bath + a good rinse - some papers need EDTA+sulfite clearing bath though...) and works very nice. It's good to have control over the hue. Just try it, maybe you'll like it a lot.
How about 5-methyl benzotriazole nitrate?