I can never stop thinking about how many parallels they have, including opposing ones. For example, their deaths.
Kaito died in peace, with hope in his heart. He was confident that his friends would be able to win and get out. He believed that Shuichi would be able to reveal the truth. He believed that Maki would be able to find the strength in herself and move on, that she would be able to love herself. Also, even though Monokuma tried to make him suffer by destroying him with something he loves, he unwittingly granted Momota's wish. Kaito went into space, as he had always dreamed of. He died before the execution was completed, thus depriving Monokuma and the audience of enjoyment. He died with a smile on his face.
It’s impossible to say for sure about Kokichi, because the retelling of events is how Shuichi imagines what happened. However, judging by the meager bits of information (and the very fact that Kaito seemed a bit reluctant when he talked about what happened), it is unlikely that things were any fun.
Kokichi died in despair and hopelessness. He didn't know whether his plan would work or fail. He couldn't know how well Kaito could (and would) carry out the plan. He couldn't even be 100% sure that Kaito wouldn't just throw away his plan as soon as he died. Of course, judging by the fact that he already had an entire script that just needed tweaking for the current situation (and I think, he prepared script in advance), he was planning on using Kaito for this plan. But still, everything happened unexpectedly, quickly and they were very limited in time. He couldn't be sure that anything would work out. He put everything on the line because he simply had no other choice. Possibly he died believing that he deserved such a terrible death. Or maybe he didn't believe he could ask for more from Kaito, so he gave him the easiest way to kill - press the button of the hydraulic press. Kokichi died with no hope of salvation and no certainty that what he did would make any difference.
