I'm a bit surprised at the graphics they have shown so far. I originally saw a screenshot and assumed it was a mobile game rather than a full-fledged AAA title for the PC.
99% of my time in Civ 5 is spent in strategic view. Keep that mode and fix that I can't tell if a tile has a coast line and you can base the graphics on the My Little Pony for all I care.
I have to admit I'm not a fan of the graphics. I had high hopes for Beyond Earth but haven't played more than 100 hours of it, as opposed to 1500+ with Civ 5. I hope Civ 6 doesn't disappoint like Beyond Earth did.
The gameplay changes themselves seem very promising, though