Add colorTable and alphaTable properties into SpriteParticle. These would be 1D or 2D textures defining the color of the particle during its lifetime. When 2D, y is selected pseudorandomly so e.g. with 2x256 colorTable you can make half of them black->yellow->white and half black->red->white gradients. Making alphaTable separately allows e.g. "flickery" particles (alphaTable quite random) while colorTable remains smooth gradients.

QDS might at some point offer UI to modify colors &alpha in timeline and store that into into PNG used for these. Also should allow selecting existing PNGs.

Particle colorVariation should probably be applied to these colors? If both color and colorTable are set, colorTable is used?

Attached some sample textures which might make lively fire/magic effect.