That's definitely something I can understand! There are things to like about Final Fantasy XIII and things to like about Lightning Returns, but those things are completely different things; the only strength they share is a good battle system. I'm quite sad that neither of the XIII sequels really featured the character interaction that I loved so much in the original. It doesn't help that the sequels screwed up the ending of the first game, which is probably my all-time favourite Final Fantasy ending.