The Visuals are stunning, and the combat is good and tight, that much is apparent. The game did a fantastic job of exploring and opening up places that we may have wanted to explore more deeply in the original version.
--SPOILERS--
My main issues are three-fold. Firstly, The story aspect of needing to have Sephiroth featured and the association with the black hooded figures (Clones) and himself. This was something revealed as a twist at the end of the original; though these individuals were found throughout the world, and became a bit of something that some may have ignored after the first few. This aligns with my second criticism which is the whispers. This was a crutch used to justify some of the story elements and was unnecessary, uninspired, and poor writing in a Deus ex Machina kind of way. All of this, just to have a Sephiroth battle at the end, which feels incredibly contrived. The third is pacing, Most of these gear items account for a good percentage of gear and items obtained far later in the story. This will lead to one of two cases, either Square Enix will not import all of our hard earned progression into Pt. 2, or they will, and the experience will be somewhat ruined for it.
As a matter of perspective, this game covers about 10% of the original game, and that can either be an incredibly good thing, or an incredibly bad thing. This remains to be seen.