"Starting to"?
I don't think there's any question at this point that this game was half-@$$ed. My first inkling was when we learned there were only 8 Disney worlds. Then we learned there was no Radiant Garden or the crew of FF that's been there since KH1, and I accepted that we were about to be served another trashpile like KH2. Only now instead of a FM to fix it, they'll be making more money via constant DLC intended to band-aid their half-baked product.
Nomura clearly wanted to get this title over with, despite the fact this was all a mess of his own making. Too bad he took so long making it. If he'd just crapped it out 3 years ago, I don't think I would've been as bothered.
Nothing about this is half-assed, and has been a passion project of his for many years. This is his baby. He clearly wanted it to be good and waited years to make it so. If he wanted to just get it over with, it would've came out in 09. You're clearly not thinking things through.
First of all, regarding the world count,....take into account that Kingdom Hearts 1 is a fantastic game and only had 9 Disney worlds that felt pretty well-crafted and relevant for the most part.
Also, KH2, while a better overall game (no idea where your trashpile comment comes in there, doesn't make sense), had way too many Disney worlds, some of which didn't even matter and were not very well designed as the first games worlds, especially for combat.
Now we have KH3, which is a wonderful balance of everything great in the series in terms of combat/worlds. 8 Disney worlds,....that's only ONE less Disney world than the great Kingdom Hearts 1, AND can we honestly even count Neverland as a full-fledged world? Not really. So technically, it's the same amount as KH1, BUT BETTER, because these worlds are much more vast, diverse, and beautiful than the worlds in KH1 with great design and room for combat.
Any more worlds would be pushing it making the game too bloated, not to mention probably diminish the quality of the other worlds in design and story like KH2 did, even though it's still a great game. This also leaves room for so much more potential in future titles.
Also, the FF characters ARE NOT needed for this story, or any story really, in Kingdom Hearts going forward. Leon and the crew served their purpose in the first two games, and are not necessary to this story finale in the slightest. To have them show up would just feel shoehorned in. If they wanna show up in future titles, sure! Why not? Create some new relevance after this for them, but as for this story, nah. Not needed. Radiant Garden doesn't need to be playable either. Let's get some new locations, yeah? We've been there THREE TIMES in different fashions. Not a big deal that it isn't playable.
And, if you were actually paying attention to things, you'd know that Nomura is not interested in DLC and said that IF they do it, they'll only release ONE paid DLC with a high amount of quality content, anything else being free. His mindset is, "Why waste time on constant DLC when we can make the next game?" Very respectable guy, there. He's not a "let's milk this" kind of dude for the money, but all about the best game that can be made for us all.
Before you try to claim it's half-assed again, make sure you know what you're talking about instead of spewing some BS.