But what is the difference if they are in hell, whether the traditional view or universalist view is correct?
Huh? Isn't it obvious? The difference is like day and night. Under the traditional view, hell inspires eternal hatred toward God in the sinner; under the reconciliation view, hell has the opposite effect. What similarities are you seeing here?
Would it be that those in hell in the universalist scenario are informed that if they repent they will get out?
Why would that be a factor? True repentance is not opportunistic. Manasseh repented in prison (2 Chron.33:10-13). There is no reason to believe that anyone had told him that such repentance would procure his release. Though he certainly wished for release and restoration to his homeland, there was no guarantee given to him of such a release. The chastisement itself, without promises attached, seems to have brought about his repentance.
If hell is designed to bring reformation, then I would expect it to be suited to that purpose. Why would it inspire eternal hatred of God? The two thieves on crosses on either side of Christ were experiencing a living hell, which they apparently deserved. It did not lead them both to hate God. One of them knew he was getting what he deserved, and repented. The other may also have repented at the rebuke of his friend, though we aren't told. It isn't implausible. In any case, we see that a man can come to true repentance and love for Christ while suffering a just penalty.
There is no reason that the execution of a just penalty would necessarily inspire hatred toward a just judge. I don't know where traditionalists are getting this idea—certainly not from anything in scripture. Does a father's discipline of his children cause them to hate him?