I thought she was great, honestly. Never felt she was too flirty (if anything, that's how I felt about her in OG, and I really didn't like it). As for lack of interest / discomfort, this is how Cloud has always been, no?

I also never felt like Aerith was ridiculously naive in any of the games. She has always been someone who has notable experience in certain areas, but a notable lack of experience in others.

Perhaps this is less about Rebirth making the characters different to OG and more about how many different ways you can interpret a character when you don't have voice acting, such as in OG.