Consider this hypothetical scenario: John Smith is a skeptic. He has read the bible but has rejected it. Jesus returns to earth and performs miracles all over the world. John Smith becomes a christian based upon seeing jesus perform miracles. The logical conclusion is that John Smith did not previously reject jesus. He rejected insufficient evidence. Once confronted with sufficient evidence, John Smith became a christian and ought to be entitled to go to heaven. If god does not wish to reveal himself to John Smith in the manner that I described, that is his choice, but I do not have a choice regarding whether or not to abandon my principles and morals and accept a god who refuses to do everything that he is able to do in order to help ensure that as many people as possible go to heaven, and as few people as possible go to hell. No amount of promised rewards and punishments could ever change that. If god wishes to impose impossible demands on me, that is his choice, but there is not anything that I can do about it.
If jesus returned to earth and performed miracles all over the world, it is quite likely that my hypothetical scenario would apply to a lot of people. Human nature being what it is, any being with sufficient power can attract a lot of attention.
Consider the following Scriptures:
John 2:23 Now when he was in Jerusalem at the passover, in the feast day, many believed in his name, when they saw the miracles which he did.
John 3:2 The same came to Jesus by night, and said unto him, Rabbi, we know that thou art a teacher come from God: for no man can do these miracles that thou doest, except God be with him.
If those events happened, then obviously PERSONAL demonstrations of power are a useful method for converting, and as a result, limiting the number of souls destined for eternal torment.