You can actually already get very close to that result, simply by changing note spacing ratio to 2:
If your music consists of mostly quarter notes (like in the autumn leaves -example), this will produce very even spacing of measures. This was also linked to the very first reply.
I think when it comes to jazz charts, it could actually be a good idea to change the note spacing value closer to 2 from the default setting. I have had to manually adjust note spacing quite often especially with drum parts, where you might have one bar of music and three bars of slashes. But changing note spacing ratio to 2 actually fixes this problem:
My feature idea would be that it could be useful if the note spacing ratio could be changed at a system break (the same way it is possible to change the space size)
Actually if also “casting off” could be turned on/off the same way, it could work very well with changing the note spacing ratio.
Anyway, I’ll definitely experiment with this the next time I need to write simple but clear looking jazz charts!