size isn't really the issue, its the unsprung weight of the car. thats the weight of the wheel, hub,brakes etc, essentially everything after the suspension, .
If the unsprung weight is heavier it will affect the following
acceleration - more mass to rotate, so more energy needed to rotate it.
braking - more mass rotating, more energy needed to slow it down.
turning the wheel - like spinning top/gyroscope the less mass the easier it is to change direction
cornering - the suspension has to push a heavier mass back down onto the road, that takes more time in comparison, so the wheel is in contact with the road for less time producing more less.
in short, if you can get a 17" wheel that weighs the same or less than your 16's it will make no difference at all.
If you get some heavy as feck deep dish bling alloys, which I doubt you will, your r will do all the things our car does a little slower and more sluggishly.
i had two sets of 15"s one set of oz polaris and one set of enkei magnesium rims. 9.8 and 4.9 kilos each. when i put the enkeis on it transformed the handelling of the car in all the areas i mentioed above. so i am a bit biased towards light weight wheels.
hope this helps.
JB