It's possible that the main story is good, and that the plots with the different LIs interesting. I haven't gone so far as to have a formed opinion of these things. Since I don't like to play with an MC like MRD's, I stopped shortly after starting. Does his personality change throughout the game? Well, unless it's something relatively quick, I don't think I'd ever see it even if I tried it again.
As you say, everything is about what each one likes, and in the end each one of us is different in what he likes and enjoys.
And I suppose that even here to discuss MRD, that neither will change what the other likes (nor do I think there is intention)