I think S-E focused too much on the villains, since most of them have proper links to the story counterpats.
To me it was a shame that they didn't use Zeromus as Cecil villain. Story wise it would make more sense, since he's ultimately the controller behind Golbez and the biggest threat to Cecil, as Golbez actually redeems himself.
They did the same for Leon, since his ultimate antagonist counterpart isn't Ultimecia, but rather Edea, yet they only used Ultimecia.
As for the FFX characters, I would have liked that they used Yuna/Seymour, that would really make a much better Hero/Villain pair.
A future release of this game with much more content and more options will be the ultimate FF crossover and fanservice ever :D
Current PC Build
CPU - i7 8700K 3.7 GHz (4.7 GHz turbo) 6 cores OC'd to 5.2 GHz with Watercooling (Hydro Series H110i) | MB - Gigabyte Z370 HD3P ATX | Gigabyte GTX 1080ti Gaming OC BLACK 11G (1657 MHz Boost Core / 11010 MHz Memory) | RAM - Corsair DIMM 32GB DDR4, 2400 MHz | PSU - Corsair CX650M (80+ Bronze) 650W | Audio - Asus Essence STX II 7.1 | Monitor - Samsung U28E590D 4K UHD, Freesync, 1 ms, 60 Hz, 28"
