are you referring to the context menu?
personally, i'd prefer to keep the commands in there as is.
it's imo already too busy!
if there are really people that use that often the non proportional stretching i could suggest an option in the preferences where you could choose if that option behaves...
but even that looks like overengineered to me.
if i understood you correctly, scribus already has a few ways to achieve your task:
- through the image tab in the properties palette... it's a click away (and you should always have the PP open on the right side... :-)
- by defining the image frame settings (in the document settings > tools > image frame) to stretch in a non proportional way by default.
- by putting a "sample" frame in the scrapbook that you can pull out and use when you need it.
i guess you can pick the one you prefer :-)