Well, of everything I would have to say I am excited most by the prospective that Nintendo is finally shaking the dust out of their heads and changing up the formula while actually retaining to the style of business that put them on the top of the pile, and the possibility that their risky gamble is going to actually pay off and put them back on the map.
With all of their failings it will be nice to see Nintendo once again a real contendor for the console wars again, and even if they don't have the ability to be competative on the hardware side of things they are good at putting out highly stylized games that look better in spite of the hardware.
So I guess that Breath of the Wild itself isn't what excites me, but what it represents.