Re: New Tires P205 60 16's
The taller side wall will certainly aid in a smoother ride IMO.
Your circumference diff is the following: Stock is 1984 mm (78.1'') vs the 60 series tire at 2047 mm (80.6'')
Speedo difference is: When speedometer reads 60mph (96.6km/h) actual speed will be 61.9mph (99.7km/h): 3.2% faster.
I would have chosen a tire that closely matches the stocker in over all circumference. I just bought a set of summer performance tires (225/45/17 almost identical to the stocker)
Not sure about any MPG difference