This is an actual question. I argue that evil can exist in Heaven.
Lucifer was a pillar of Heaven's community. Lucifer was known as the most beautiful angel until while in heaven he turned against God and raised an army.
God is arguably perfect because he is without evil. Heaven can not be perfect if it can have evil inside of it.
Can you argue these points? Lucifer turned against God while in Heaven and under the influence of Heaven. Heaven, therefore, can have evil and is thus not perfect.
It all really depends on what definition of "Evil" you want to use.
If we use a rather "traditional" definition, the "Seven Deadly Sins", the answer is a strict
no, with one exception.
Gluttony and Lust are both attachments to physical pleasures. In a world of spirit physical pleasure is impossible.
Similarly Sloth is an attachment to physical comfort. Again, as this sin is physical, it cannot exist in a non-physical realm.
Greed and Envy are all about physical possessions, impossible to have in a non-physical world, so they are impossible there as well.
Wrath is about a desire for vengeance against physical slights you have suffered. In a realm where you can suffer no slights or harm, how can this evil exist either??
Pride is about an attachment to your own self-image. It, alone, of the traditional Seven Deadly Sins is the only evil that could potentially logically exist in the common conception of what "Heaven" is. And that even fits in with what you are saying because the story of Satan's rebellion says it was due to his Pride. So maybe you are right. The evil of Pride could potentially exist in Heaven.
Potentially, at least. There's an argument to be made that a prideful person would not be admitted to Heaven. And notice the moment that Satan develops Pride, he is cast out of Heaven.
Assuming this is the usual case, one could state that the moment one develops the one evil that does not require material objects to exist, they are cast out of Heaven, therefore Heaven has no evil within it at all.
But, again, this all depends on the definition of Evil you want to use in the first place, but it is an interesting theological thought none-the-less.