[MeinBlutIstBlau]

As a just average Joe gamer, art style makes or breaks a game. If you pick a style, stay with it. Indie games like stardew, skullgirls, don't starve, papers please, punch club, and darkest dungeon all proved graphics don't sell games, especially on mobile. If anything word of mouth has probably helped most of those. But mostly, the art style is visually appealing and doesn't look like lazy garbage.

[jmiskovic]

More actionable, the choice of colors and their combinations is the key ingredient for cohesive and tight art direction. Pixel art, vector art, low-poly 3D - they all rely more on good colors than on shapes.

It's quite hard to pick each color from color picker wheel and ending up with something decent. Much better approach is to use pre-assembled palettes like ones on lospec.com/palette-list collection. My favorite versatile palette is edg32, but others will work better for certain moods. Working with more than 30-is colors requires experience and patience.

These guidelines can help to build something that catches attention, and assets tend to be simpler and easier to iterate on.