Some sin - earthly punishment, then infinite punishment.
Worse sin - worse earthly punishment, then infinite puinishment.
Total punishment for all kinds of sin: infinite punishment.
In the end, no difference - you think about cheating on your wife, you get hell; you kill fifty people, you get hell.
Well you can pretend that the Bible doesn't teach different punishments for different sins, but you'd be wrong. Not sure what else to say. I'll try to illustrate though.
Let's imagine two scenarios.
First, you insult your wife. Offended, she kicks you out of the house ("take your stuff and leave!"), and you are forever separated from her, never to be with her again.
Second, you cheat on your wife. She smashes a lamp over your head. She then takes one of your golf clubs and hammers you with it. She then smashes a mirror in your face. She then spends the next hour beating you to a pulp. Then she kicks you out of the house and you are forever separated from her, never to be with her again.
In both cases you are kicked out of the house and separated forever from her, but clearly she views one offense as worse than the other. The END result is the same (kicked out) but the path to getting there is quite different.
Plus....the James 3:1 text indicates that there may in fact be degrees of punishment even in the afterlife. So who knows.
But hey, you seem committed to this line of thought, so it doesn't appear that anything I can say here will dissuade you from it, so believe whatever you want. Makes no difference to me.