I have been working with the Grouped lines for a while now and I have some issues that is problematic for me.
That is why I still hope you could add the LINK POINT feature to the rectangle object?!
Just to summarize,
* normal lines do not have Link points option (1+2)
* when I connect and group lines then the Link Points option show up (3+4+5+6)
* when I look for Link points in a normal rectangle I do not find it (7+8)
What I miss is this:
* text label in the middle of the rectangle (and free label is not good)
* background color, both looks better and is easier to handle/grap with the mouse
* size adjustment using the Properties dialog
* and more
I hope you understand
Have a nice summer