Well it's true that he can deal large damage to certain Magus characters, he falls short due to his low usefulness outside of that. He's pretty much good against only Magus, and that's it. He falls to Warrior characters with ease, is completely negated against Magus Eddies like Seventh Son and Crusader, and Edward the Great was specifically made to counter him. He is good, but he's not very useful outside of his specialty.
Well the sleep point was to show that he requires certain teammates to get the most out of abilities, which I don't entirely find helpful in a game where a team with variety is key. Venom Talismans are nice, but I could then argue that Beast Eddie should be higher because you can thrown Venom Talismans on him as well and he has the same upsides. Permadeath can be cleansed, whereas Perfect Death cannot be and is easily inflicted by certain other toons. Stained Glass is an amazing move though, and I will agree that he is a good Eddie. He's just not as good as some of the other top tier ones. He's perfectly balanced for a 4-star, in my opinion.