Like a lot of Slott's work, Red Goblin is an idea that can work if someone other than him is writing it. So I am curious to see how this series will work.
My one issue with Norman becoming Red Goblin is that in place of two villains (Goblin, Carnage) you now have one. I am against stories and concepts that whittles down and makes unusable one or more of Spidey's rogues at any time. Obviously there are exceptions and so on but I think after Norman's resurrection, you don't have an excuse as a writer/editor to try and do some lasting change and try and sell that as sticking.
I think the PS4 game and its sequels will feature Red Goblin. The finale of the PS4 game implied that Harry Osborn is being bonded with Venom and that Norman is working on that. If you have Harry Venom, then eventually you are gonna need Norman being a bad guy and you will need Carnage. So Red Goblin makes sense.