One of my biggest feature requests and something I would really like to see in this program is a dedicated cropping tool, either as its own tool in the sidebar or an extension of one of the existing tools.
This tool would allow the user to freely grab one of the four edges or one of the four corners of the current project’s canvas and drag it out to change the size of the canvas. This would make it slightly faster to expand or reduce the canvas size without having to go into the canvas size tool or cropping to the selection (which only works for reducing the canvas size).