This addon is top notch, and by far one of the most fleshed out weapon mods on the workshop. However, even though it goes against the principles of the source games, I believe that many people would like the option. Just a simple toggle placed in the menu, off by default so that only people who care for it will have to bother.
I'm not good at all when it comes to modding and changing code, so I don't know what it would take to include the toggle for a crosshair, but I am sure people would appreciate the effort.