Don't you have to be undead to live eternally? What happens when you grow tired and bored to death of eternal life? I love sex, there would be no need for procreation. So how can I do the thing I like best in an after life? What about my favorite foods? I wouldn't need to eat? I don't have to create a reason for my existence, I was born and that has and been good enough for me.
You can go beyond these things and include more, like hobbies, entertainment like sports, plays, movies. If things are always "great" does this mean that things always go your way, you always win? There are no "losers" in heaven? Your sport team always wins so that you will be happy. The movies you watch are always great? But usually what makes a great movie is the conflicts, the struggle to overcome adversity, but wouldn't these concepts not exist in heaven?
It seems to me if heaven existed you would be in a perpetual state of bliss but you actually do NOTHING. You don't experience anything at all. Like a person on a heroin high but constant and unending. You don't do anything. You don't talk to people, you don't experience anything other than this spiritual high. Like a mindless drug addict who never has to worry about another fix because the high never comes down.
Anything other than that, just doesn't make any sense to me. Just imagine if you saw a family member who abused you, molested you, mistreated you your whole life. They managed to get through the loophole and make it into heaven and now you get to spend eternity with this person? Or how about the flip side where a person you loved deeply didn't get to go to heaven and instead they are suffering in hell for eternity.
You would just be fine with that? Or would god create an illusion version of this person and pretend as if they were with you in heaven but in reality they were really in hell? How could you enjoy heaven knowing that your loved one is suffering? But if there is no hell and everyone gets to go to heaven and hell was just an attempt to steer people into behaving, then heaven itself would lose it's value. If every asshole gets to go and now you get a constant reminder of you can be the biggest douche bag and still end up in heaven with all the people who weren't assholes.
So for me there are just too many conflicts and issues. To me it just seems more realistic that there IS NO afterlife. It has far less conflicts and difficulties. It is easy for me to imagine non-existence because all I have to do is think about where I was before I was born. I have no thoughts or memories of before being born. That same oblivion will return to me one day but I won't even be aware of it. I am fine with that conclusion because eternal happiness just doesn't make any sense.