Personalize shortcut modifiers & new shortcuts

[Pi7on]

Hi, I'd like to request the possibility to assign to each shortcut not only the letter or number, but also the modifier.
For exemple, now if I press ALT while I'm drawing a Bézier curve, I can move one of the handles freely to create a sharp corner. 
I'd like to be able to do that by pressing SHIFT instead of ALT.
Also, to translate and object in a straight line, I must hold SHIF, what if I want to use CTRL?

For a second sub-request, I'd like to ask if it's possible to assign more keys to shortcuts, for exemple, if I'm using whatever tool and I press ESC, it could give me the move tool (I'm weird, I know). But at the moment if I try to assign ESC to something, it just closes the settings window.

I'm requesting theese because I used Inkscape a lot, and it has these mechanics I really liked.

So to sum it up, I request more freedom about shortcuts assignement.

Hope you can implement it, have a nice day