I've been meaning to revise our "RomanS" (no I wouldn't keep it named RomanS because of the following reasons) to take some of the never used symbols that are easy to get to on the keyboard... maybe ? and _ or something... so that would could have PL, SL, and CL without jumping through hoops. I think your idea about putting the slash through the zero would be great, because often we dimension the overall of something and add "O/O" to the end, to denote out-to-out, and it always irked me, especially when you see
|<------------ 100'-0" O/O -------------->|
in a font with too-similar Os and 0s.
Good idea, I might take a look.. I had read through the chapter in the Autocad "Customization" book that covers fonts, but it may help being able to see my original RomanS, and see what is different for the "O" than yours. I often learn by example faster (maybe not better, but faster) than shooting from the hip until it works right