The only way to know what gear will work for sure is try it.

48x16 is probably a little high for most people just riding around. If you are an aggressive rider willing to work or pretty strong already then it is probably a good gear.

44x14 is about 83 gear inches. This is a pretty high gear for most people on the road, especially with hills. .
39x14 is about 73 gear inches, about 13% lower.

48x16 is about 79 gear inches. This is what I run but again, what works for me is not necessarily good for anyone else.

It is probably good to start around 70 gear inches and see how it feels.

BikeCalc.com - Bicycle Gear Inches Chart