If atheism is right, both Christians and atheists end the same.
If Christianity is right, then most of the atheists go to hell to burn.
Pascal's wager is a probability based argument that says that we should believe in God to increase our chances of happy afterlife.
Now, no matter how many other options are there besides atheism and Christianity, it still logically follows that being a Christian increases your chances of happy afterlife more than being an atheist does.
There are basically these relevant options:
1) There is no God - Christians and atheists end up same
2) There is God who punishes Christians and rewards atheists - Atheists end up better than Christians
3) There is God who punishes atheists and rewards Christians - Christians end up better than atheists
The option 2) is the only argument against Pascal's wager.
If option 2) is proven less likely than option 3), then it logically follows that Christians are more likely to have a happy afterlife.
But how likely is the option 2)?
Is option 2) more likely than option 3) or equally likely as option 3)?
I would say not even close. First, if there was a God who rewarded atheists and punished Christians, such God would have to be immoral since most of Christians have similar or better morality than what atheists have. Therefore, the only way to argue against Pascal's Wager is to assume that immoral God is just as likely as moral God, and to assume that such immoral God for some reason prefers atheists over Christians. Such God would also need to be unreasonable God, since its unreasonable to prefer atheists when there was no proof or even a hint given during our lifetime that atheism is the correct path.
Second, the greatest religions on Earth are against atheism. So the God who prefers atheists for some reason created religions that are implying how atheism is wrong. These religions are all built on morality. Therefore, God who prefers atheists would punish those who follow morality.
So any God who prefers atheism would have to be immoral and unreasonable.
So, if we know that there are only 3 options for afterlife:
1) Atheists and Christians ending up same
2) Atheists ending up better than Christians
3) Christians ending up better than atheists
Option 1 is neutral, therefore it doesnt affect happy afterlife.
Option 3) is more likely than option 2), since moral and reasonable God is more likely than immoral and unreasonable God who prefers atheism.
Therefore, we can say that Christians are more likely to have better afterlife than atheists are. Atheism just doesnt seem worth the risk.
Now, I am not one of those Christians who believe that all atheists go to hell. In fact, God rewards according to good actions that a person does. We cannot say that all good actions of atheists will be negated due to atheism.
However, if a person is an atheist, it does increase his chances of being immoral. For example, most of the atheists are in favor of abortions, in favor of LGBT.
So it basically comes down to morality of a person.
Is fun worth the risk?
Its not even worth the risk in this life. Plenty of sexual partners make people depressed and suicidal. Alcohol, drugs, speeding... any sin really makes life worse.