I can see where your coming from, but I think it could also be seen from the opposite perspective. The main message of the route “Live facing forward”, while I wouldn’t go so far as to say that it suggests one should leave everything in the past where it is, just in the past, but it makes me interpret the end of the stories as “the characters only have one direction to go from here - forwards”, and that while I agree it’s important to carry their emotions with you, both you and they should keep moving forwards.
Actually, it just occurred to me, her lack of emotion might exactly be the reason she does such outrageous stuff all the time. She’s trying to get a reaction out of people, maybe for the sake of observation or some such matter. I think it’s at least fair to say that she has a motive beyond “because it’s fun.”
(Refrain spoilers)
I have to object to what you said about it being inconsiderate. They were under the impression that after the dream world came to an end, they would die, that Riki and Rin would be the only survivors. I think what Kyousuke’s doing, giving them one last chance for closure - to sort out their regrets and have fun - and be in love, is a very admirable (although admittedly, a side-effect) part of his plan.
