Good free software for creating textures?

I am trying to create and edit textures in minecraft.

The most recommended free program seems to be GIMP. But I'm not gonna lie, the experience with it is terrible if you are trying to draw anything. There is no color palette or simple drawing tools. There is no shape drawing. The most you can do is move pixels around, brighten or darken things, or add text.

What are some free programs for actually creating NEW content rather than adjusting existing content?

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