I honestly think Raimi should've given Bruce a villain role in the first place. His voice just screams "Mysterio" to me for some reason. Maybe because he sounds like the way Mysterio sounded back in the 2000 Spider-Man game for PS and N64.
Assuming the producers and, more importantly, the studio let that happen. I've always assumed that Raimi post 1990 (the year he made DARKMAN) has always been willing to give Campbell bigger roles in his projects, indeed including the lead role in the aformentioned movie, but the major studios have time and time again basically nixed the idea of Bruce in a huge part.