After what Raimi did to Venom in the third movie, I would NOT want to see him do Carnage.

Carnage brought a whole different kind of evil to Spidey's world that is not suitable for kids to watch. Firstly, the serial killer Cletus Cassidy was introduced when Peter was well into adulthood, with adult problems and he was already married to MJ. Secondly, he is extremely psychotic; like Joker times 10 without any humor. Finally, There is no real way to introduce Carnage into the movie without establishing Venom as a real character first. What, the movie starts with a barely even seen Venom giving birth to red goo that somehow slips onto Cassidy? Don't think so.