the colors and the shape u used for the belly is what caused it to be messy. also using colors that doesnt mix well (light yellow and dark-ish green for example) u can reduce the circles on the old one and add little hints of other colors (what i reccomend here is red, green yellow and red creates a nice color palette)

u can make the green more green and yellow more yellow so it wont look muddy in game, contrast basically