I think this game being about Aqua ties in nicely. It still doesn't contradict that she didn't really go through a decade as Nomura confirmed about when she talked with AtW in Blank Points, and if we say it's been something less, like a couple of months, it makes up for the time span of an average game (CoM was a special case with taking like a month, but everything else took longer if only for the inter-world traveling [Days had other reasons for being long... mostly Nomura's shenanigans but still]). I think it'll be fun, writing down Aqua's RoD timeline and see at which points in time people from the RoL came over (I can imagine Mickey and any appearances Riku made will be rather close to each other, which'll be nice, creating the illusion they're related to each other in that sense)
It can also tie in nicely up to the future of the series, but the only way in which that'll work is if it'll have another dreadful ending, something along the lines of BBS. Otherwise it'll contradict her state when she met AtW. At least it will really explain why she seemed so exhausted at that point. I prefer her going through a journey rather than her just being worn out by the Darkness, especially after Ven and Terra's Keyblades (which I hope will be confirmed to be not the real things, but their RoD Matches) saved her, giving her a bit of hope to carry her on