>>11957382
In hindsight I should have said that fullbright *can* compound issues with limited palettes. I don't think it's necessarily a mistake. I'd say it's a split between level design and graphic design. Any way I slice it, I can't imagine simple, wallpaper-like mapping going very far. What COLORMAP isn't able to do for you (anything, I guess), you'd want to make up for even more at the texture level with eyecatches like situational textures, large details, and background elements. Depending on the scale you're working at, that's a big custom job.

>dithering and a lot of pitch black for shadows
This is what I would've brought up, so good on you. Going for darker games definitely works to your advantage. I'm sure I don't need to say this, but never be afraid to let black be the dominant color. My favorite example to point to is Action Doom 2. Some maps might have been more black midtexture than not to give everything that cel-shaded look, and it's very emphatic with textures that only exist to be used as background detail.
Also, look up FrankenGFX. Really pertinent art, and her stuff is NES-displayable.

>>11957490
>did it even have any cultural significance for the last 30 years?
Eh, it's never making waves on the level of nu-Doom, but it's had several spinoff series and still inspires a couple games every year like Berserk Boy. About as much as you could reasonably expect from a series this old.