I completed XIII-2 this afternoon. The end boss went from ridiculously hard to ridiculously easy after an hour or so of levelling. Did it first time round and whereas the last time I was relying a lot on paradigm shifts and keeping track of everything, there was no such need here. I blitzed through it pretty easily. Funny how the difficulty shifts in such a huge way like that. Hell, I even got the achievement for getting a 5 star rating on it.
As for that ending? The less said the better. I think it's certainly a better game than XIII, as in, there is more things to see and do that improves the longevity of it but I couldn't give two shits about the story throughout it. Now, every FF game has it's share of clunky dialogue, but it was just more prevalent here. I don't want anything more to do with XIII's world or it's characters.