I've wondered if Norman being a little more on-the-ball is a result of not knowing Spider-Man's identity anymore. So even though he still hates Spider-Man, he doesn't have that "my son's best friend" angle to obsess over.
I'm guessing Norman's obsession isn't *just* from the fact he has Tony's old job. It's also the whole "nano-controlling Norman into attacking some Atlanteans" from CIVIL WAR: FRONT LINE. If anyone remembers that revelation was in FRONT LINE #11 (not just Sally Floyd's "Americans use their freedom and liberty for NASCAR and YouTube" speech).