Use AI to generate app images

As an indie dev, my biggest cost is hiring designers to create the images when I create a mobile app.

For 2d games, I need to pay to create spritesheets.

For utility apps, I need to pay to create the menu images, simple images, etc

Is there an AI tool that would allow me to do that?

I tried DALL-E 3 and midjourney, but the results are less than satisfactory. The main issue is that the consistency of images is not there.