I wouldn't mind paying for a plugin or software similar to ImageReady from Adobe, with the same quality and tools (like text & shapes), so no obvious dithering and unlimited sizes.
I'm not in a hurry as I still have ImageReady 6 but it might get obsolete in future OS updates of Windows.
GIF animations are important for Twitter because video is so badly compressed there that it looks worse then GIF.
Here is an example of the sort of thing I make with it. Text is created in ImageReady, the dark gradient layer at the bottom comes from Affinity photo. The images themselves are imported as layers and then tweened. As you can see, the quality of the images remain quite good, notwithstanding the adaptive 256 palette.