Well, I mean, to at least the die-hard fans, they'd sell like hotcakes, but I do see your point. And as far as KH cloud goes, I think that makes sense; Dissi is a Final Fantasy game, and while KH is a Squeenix game, it wasn't part of it to begin with, so why put it in the second? I like the outfit idea though.
Probably not, considering that the KH team wouldn't need to do any work in either case. I can't really say why they didn't want KH Cloud in Dissidia, unless they wanted to keep the KH versions of FF characters out of Dissidia for some reason. The Final Mixes would only take translation, no porting, the only likely reasons that we don't get the FMs is because they are made to be Japanese exclusives, like the International versions of the FFs. Another possible reason could be Square-Enix not believing that the FMs would sell well enough in other countries after releasing the initial versions to justify translating them.
Yep. I'm hoping they offer these costumes on PSN at some point, so people who buy the games after their initial release can also enjoy the costumes. Although, if they bring over 3rd Birthday as well as the same pre-order bonus, I may have to get it. Hopefully KH Cloud will become a pre-order bonus for Dissidia Duodecim here since I doubt we'll get BbS FM. 3rd B-Day Lightning is awesome, but KH Cloud's the one I want the most. More so then that though, I want a complete DDFF, which means I have to get those pre-order bonuses in some way.