>>7724349
>>7724962
>>7725283

yeah, the painting method I've been using to make old computer-game-style portraits might be similar. I start by doing either a flat colored drawing (top) or a painting (bottom) at 2000-3000px, shrink it to about 320px, then draw over the outlines with a 1px pen (in CSP, either millipen with "1px minimum brush size" or real g-pen with no minimum for broken lines), then proceed similar to how I'd cel-shade a drawing:
>flat color
>multiply layer (all coloring is done with lasso fill, antialiasing off)
>overlay layer with mid value colors to add saturation to areas
>soft light layer to add more range to shape the form
>normal layer on top to detail things like eyes, mouth, highlights
attached pic shows layers for the bottom one (color burn layer is just to add freckles)