I know that remakes and remasters are contentious, but let's pretend whatever game in question you're thinking of is handled with the utmost care by your favourite devs and they absolutely nail it.

Mine would be Shadow of Memories (called Shadow of Destiny in North America). It's legitimately one of my favourite games of all time but it kinda flew under the radar and I haven't met many people who know of it let alone played it. Seeing it get modern graphics, maybe some expanded mechanics, would be soooo cool.