worth the jump to Cornwall IV's from Forte IV's?

Check your measurements again. The La Scala about the same width as a CW and  is only 10" deeper. It can also sit flush against the wall.

And as @ozzy62 pointed out, the sound is something to behold, subs or not (as in my case). My advice is to not sneak up on what you want; just plan and go for it. It will cost less in the end.

Aside from being an incorrect blanket statement, do you see your second sentence is a non sequitur to the first?

"All Klipsch speakers need Dynamat placed inside the cabinet to yield the best results. Ive had ALL of the Speakers mentioned above except the La Scala’s and Heresy."

My Forte IV, La Scala II (two pairs) and Heresys never resonated or needed anything from me to sound great. 50 year old Klipsch (like any other old speaker) may need some acoustic treatment for best performance, but the op is discussing new speakers. I don’t think Ozzy or I have used Dynamat on our horns.

Greg makes several Volti speakers which are as large or larger than the Klipsch counterpart they are modeled from. They are great speakers in their own right.

I live alone and never had an issues moving any Klipsch speaker.

And its a problem the Forte is unforgiving for poor recordings? What the solution; buy poor speakers so you don’t notice or stop listening to poor recording? You chose.