How about adding a new frame parameter: "parent-frame"?
 
Then we can create a new frame whose parent frame (e.g., hWndParent) is current frame, and the new created frame always shows in front of its parent frame even we focus on its parent frame. Then the new created frame is like a Dialoge window opened from its parent frame.
 
I think it will be quite useful. e.g., when we are doing a "ediff", it will be nice the the "ediff" frame always show in front of the "comparing" frame. When we click on the comparing frame, the "ediff" frame will never be hidden by the "comparing" frame. And so we can easily access the "ediff" frame again without having to find it back from the task bar.
 
We can also use this mechanism to utilize a frame as a dialoge, to provide a complicated text-based (with image) dialoge window. It will be cool when a command need a very complicated input from the user.
 
Regards,
Brian