Heaven is not a place where 'only good people' go when they die. It's more like a large place with endless possibilities.
There is no evil there, because no one wants to harm anyone else. There is so much love and positive energy there that evil can not take place.
We are still free thinkers, but not quite the same as here on Earth. In heaven, we can build anything. We can do almost anything. We are not 'gods' but we are not really limited in what we can do. Picture it as building your own 'world' but with almost no limits on anything.
Many people actually despise heaven, because they think it's all goodie goodie and boring...no. It's nothing like that. It's could be more like everyone is there for a good party and festivals and dancing, music, laughter, food, beyond beautiful landscapes, and just anything good. When there say there is 'no bad' they mean that there is no death, no loss, everything is equal, no wrong upon anyone. Stuff like that.
Heaven is a place where the energies are all positive and everyone is happy.