I would also like to add:
-Set origin and image points with numpad behavior: When an animation has multiple frames, the quick assign with the numpad keys is dysfunctional. Instead of assigning the corresponding position for the image point, most of the times it changes the selected frame or, if that frame number doesn't exist, it prompts a notification sound. The only coherent and reliable way to use the numpad for assigning image points (after you select the Set Origin and Image Point tool), is to first select the desired frame with the mouse, then click within the image editor to place a random point and, finally, hit the numpad keys for quick assign. Repeat for each and every frame.
As it is mentioned, advancing frames should be done with other keys like ctrl + arrow keys and the numpad keys should be left to do the placing of the origin point at any time, even if an other tool (e.g. brush) is selected.
-Add an indicator in the color palette. Just like the horizontal level bar has an up looking arrow (which is very helpful), add something (like a cross) withing the color palette in order to visually know which hue/saturation is currently selected.
-Add option for lock proportions when rescaling images. If you have an irregular in dimensions image like 460x 234 and you want to half size or 3/4 size it, you need a calculator. Ideally, the Resize Image Canvas tool could have the functionality to do math in conjunction with the locked proportions. So, in the dimensions mentioned above, one could put 460/2 or 460*0.75 on the Width field and get the desired result on both dimensions.