For some time, you enabled a keyboard shortcut (Ctrl-something) that allowed to delete strokes without needing to select the rubber tool. I had used it and found it very convenient, but this feature has disappeared in your latest versions. Could you bring it back?
Apart from this, here's my proposal for two new features that could be interesting:
1.- The possibility of drawing straight lines by holding one of the mouse buttons (much more practical than having to select the ruler tool)
2.- Improving shape recognition: It works fine for circles and ellipses but cannot recognize squares or triangles.
Thank you very much!