First off, if you still have a stock output shaft, it's best to go with a bigger front sprocket as it's easier on the output shaft. Then make up for it on the rear. An 18 minimum, 19 ideal. Plus a bigger sprocket also helps the rear end squat a bit due to having more leverage on the chain.
I don't have any suggestions for a 16 front. However on my personal bike I run a 18 front and I wanna say a 44 or 45 rear for street/strip use. In the winter time when I do a lot of long rides, and highway bombers I'll put a 43 on the rear as it helps to keep traction on the colder roads, and keeps the rpms lower on long rides.