The easiest to do would be Rocky and Bulwinkle. You can basically make a very nice color pallete based on pixel brightness (basically DMD Extender style) R & B is the VERY BEST looking game for this!

Skip to 3:45 of this vid to see it

It is 4 color. IIRC: white, tan, brown and black. That pallet is for the entire rom (not scene)

Every character is consistent throughout the rom. The 4 colors work with each character.

Most roms, have characters that varies (pixel brightness) per scene. R & B doesn't. Its consistent

Its my vid, utilizing pinmame - with colors set pet pixel percentage. The pinkish looking was probably my [EDIT] tan,
I used no tricks, no hacks, but my camera - monitor viewing angle might've altered colors slightly.I dont have pinmame running on any of my current PCs, but anyone can verify using pinmame.

EDIT ~ The tan definitely appeared pinkish.

Colors must've been: White, Pinkish Tan, Brown, and Black

Disclaimer: I have never owned (nor do I wish to) a R&B. I was just a person that discovered that games consistency within the pixel brightness settings (via PinMAME) and found a single color scheme that worked well.

I have a DMD Extender, and used it on a couple games (JM and HSII).
I messed with most every pinmame (with a dmd) game. R&B is the only game that I could make that consistent nice characters within PinMAME (DMD Extender styled)

Will Elis board work with P-ROC? I believe the timing cycles are different than other systems.