Final verdict: there's not nearly enough of the original cast - the reason I love XIII so much is because of all the relationships between the characters, so it saddens me that we see so little of those relationships here

I've heard this from at least one other person, and to be honest, it's the reason I don't think I'll actually invest in the game and play it myself. I loved the original cast so much I think Lightning Returns would be ruined for me just from wanting to hang out with them again.