Welcome to the forum.
I had never heard of the MV Agusta F4 750, and now that I searched for a few images, I'll give my input. It is not to be taken as gospel, just my perception.
Considering what you said about your physical comfort and age, I can't see how a modified CX in any form could ease you.
This GL500 Silverwing Interstate was completely restored when I got her a few years ago, and at my age of 60, with my ailments, could not trust myself to be safe on the road with her......so I gave her to my good friend here, WiscoKid.
The ailments you possess certainly dictate what you can and cannot be comfortable with, but above all, if you can't be safe and in total control, no bike will suffice. And that is where I stand now, bikeless.
I can't speak much to bobbers or cafe's based on the CX/GL line other than some are visually tasteful, yet I would have never gone that route. The pure stock form has always been more my eye. I've had three variants over 15+ years.
It would seem to me, based on what you stated, that you would likely be unhappy with the options you pose.
As I said, my 2 cents only.
Joel in the Couve