It is nice.
This is not a case where the game is coming in one or two months after the demo / beta. the game is only 60% complete and still has a long way to go. It is possible that the game will have frame issue, sure. But making a judgment as of now doesn't make sense.
Mainline Final Fantasy games never lacked polish. ( leave LR out of this ) heh.
The engine already stands. the missing 40% are not optimization but content. Look at the FFXIII demo which also was based on an early build. Apart from the different menu design it was virtually the same as the final game.
And this is always the case. With every demo or "beta" nowadays. People let the devs get away with everything saying "All criticism is invalid because it's not the final build and everything will be better in the final game!". Which is pretty much never the case.
I don't really believe in the FF polish anymore after I've seen LR. It's a different time and the machines are weak. Devs these days just love to sacrifice performance for spectacle. And you know how much SE loves spectacle.
If you demand respect or gratitude for your volunteer work, you're doing volunteering wrong.