Given the nature of what you're trying to do, arguably, there is very little for you to do. As you've already observed, "normal" human visual acuity is already

Given the nature of what you're trying to do, arguably, there is very little for you to do. As you've already observed, "normal" human visual acuity is already wildly incapable of perceiving 2^256 different possibilities as distinct anyhow. If normal humans are 200 bits short of the desired 256 (and I'm still feeling generous claiming we could distinguish 2^56 different images of this type, but it's a nice round number to make my point here), color blind people are 203-ish bits short or so. It's not that materially different. Normally when discussing being color-blind sensitive we're discussing not embedding 2 or 3 bits of information into colors that can't be distinguished by those who are color blind, but in this case, we're trying to jam massively more bits than anyone can handle into an image, so it's not clear that much is called for other than tweaking where the bits get lost a bit. Or, to put it another way, relative to the desired goal, we're all already massively "colorblind". Those who are what we humans would call colorblind are, in relative terms, hardly at a disadvantage at all for once, because we're all so many orders of magnitude short of the mark.