This has been the toughest of all to pick. My two favorites!

I think FFVI wins music hands down. It was the pinnacle of 16-bit era music. CT has some great tracks but I love almost every track in FFVI. As for replay value, as some have mentioned CT literally has content that you need to replay in order to see. You can technically see everything in one play through of FFVI. It's also a massive game which makes it harder to pick up and play over again. I'll have to give CT replay value.

So for the tiebreaker I'm just going with the game I like more, which is FFVI.