I have to believe that such features would seriously up the price of the comic.
I like some of the feature ideas, and given that the comics are presumably assembled as layered image files, being able to turn things like lettering on/off shouldn't be a big deal, but the creator commentary sounds dull as hell. Can you imagine Jim Lee explaining his "creative choices"?
"So on this page, I drew Lois Lane with big tits because... um, well I really like big tits. Also I threw in some pouches."