As an enemy, Venom brings things to the table that not even Norman Osborn has ever been able to, and vice a versa. For example, Venom knows how to hurt Peter Parker far better than Norman is ever likely to, he can easily sneak up on Peter and kill him without warning, and push Peter to the edge by taunting him and reminding him of that. He may not kidnap Peter's loved ones to draw Peter out like Norman does, he's not above threatening them to prevent Peter from turning the tables on him. Harry's debatable, but Venom is, without a doubt, a far better foe for Spider-Man than Bart Hamilton. That's just ridiculous.
That all said, Green Goblin does deserve a game.