Digital BW, The Print

I use an R220 with the MIS UT-R2 neutral ink set primarily on Innova 
315 Smooth Cotton and Dourian Art (Photorag clone) papers.  I've 
found myself using black only more and more simply because I like 
the warmer tone for some of my images.  I am interested in the UT-3D 
inkset, but not ready to commit to it until more profiles are made, 
and not sure Clayton's driver control method is a step forward from 
the ICC approach I use now.

I saw Paul Roark recommends using a warm yellow cart to slightly 
warm up the neutral set, but this doesn't make a whole lot of 
difference in my experience.  I'd like to split the difference 
between the neutral and warm set.  If I bought a warm yellow bottle 
and used it in say the LM and Y places, would that get me close to 
halfway to the warm inkset?  Any recommendations as to what might 
look good while minimizine strange shifts in toning from cool to 
warm?  I thought I'd ask before blindly experimenting.

Also, I've given up trying to get the Epson semi-matte to work on 
the R220.  If anyone wants 200 4x6 sheets or so for proofing, it's 
yours for $20 + shipping, or best offer.

Thanks!
Roger