Possible/rational to do a custom ink color mix ConeColor Pro?

1

In looking at a P400 I note that the ink colors are a good mix for my work–mostly printing art, not photos. But green ink would be nice. Some of the bigger printers have reduced the number of colors to fit in a few mid-grays, which I do not need since I use PiezoBW.

Is it possible, and also sane, to do a custom mix of Cone color in refillable carts? It would require a custom profile or RIP, which seems complicated. The P600, P800, P6000 and P8000 have
C, VM, Y, PK, LC, VLM, LK, LLK and MK
I like the idea of having light cyan and light magenta, but it would be great if we could drop the two light black inks and replace with orange and green. I note that ConeColor does not have a red ink. I guess magenta+yellow handles that pretty well.

Crazy-talk?

The P5/7/9000 have all the inks, but are expensive machines. Also, only the P400 has a GlossOpto. ink.