I don't understand (a) why the afterlife is necessary, and (b) why it is assumed that if we behave appropriately in this short life, we will benefit from eternal bliss. What would eternal bliss be like anyway? There are some pre-conditions if it is to mean anything: 1) we would retain our identity independent of our early bodies, and be aware of our previous living persona, 2) we would be aware that we were in a state of bliss.
I find point 2 particularly hard to reconcile. As humans, the thing that enables us to enjoy the experience of happines is having opposite feelings. Just as a spoilt child does not appreciate the struggle to provide food and clothing, because they never go without, so surely would we be unable to appreciate bliss if there were not regular contrasting reminders of unhappiness or pain.
Hmmm. All seems most unsatisfactory. Delighted to hear other views, preferably not the type that say it will be so because the Bible says so. That does not cut it for me.