I would love an alien (rather than human skull) feeling pack that mixes bio & mechanical elements. Whatever size fits a 48x48px character best - depending on the scale of the elements, that could be 16x16px or 32x32px. Ideally it could "match" https://samvieten.itch.io/metroidvania-pixelart-tileset-biomes in terms of palette, scale, lighting, and style.