There are some amazing news! Thank you
I guess scale slider was the main reason I didn’t use the fill layers. So scale and rotation sliders would be the most important for me at the very top. Not sure if distinguishing between x and y scale axis is needed, but it would make some sense to have a link toggle between them like in scale or resize canvas (if people decided this distinguishing is needed).
About other transformations: perspective transformation (like this when you press ctrl and draw outside the object) would be great, as it would be a first way to get non-destructive perspective transformation. So this would involve two more sliders I guess.
But those, and other transformations you mentioned are not that essential as scale and rotation, so it would make sense for me to place them all in a collapsing block under scale and rotation (collapsed by default, to simplify it a bit, as those wouldn’t be used as often)
Oh, and I nearly forgot: as I see in further plans you have allowing those transformations to brush engine too. In this case a toggle “link texture scale with brush size” would be amazing, as it was already requested here some time ago.