Theres three windows, the image editor, the frames editor, and the animations editor.
I haven't criticized anything, I suggested placing all that was suggested into the animations editor, that we don't even need currently as it could be integrated into the image editor since all it does now is work as a simple list editor.
A sprite sheet requires the frames to be stitched together at some point. That either happens before it is imported, or after.
The odds of getting features to do that in the current image editor are extremely low.
Im saying all such editing of animations should happen in an animations window.
I don't know how to say it any simpler than that.
That's with 17 years of game development, 9 of which are with Construct.