I'm doing just fine with 80 gear inches. But my legs are built for it. You are going to have to find out what you like on your own I bet. Using a gear inch calculator like above is a good guide.

Just remember that spinning can buck you out of the seat, so downhill get a brake. Also spinning will make your knees happier and the hills easier. That being said I went up from 44/15 to 49/16 and went faster. I'm not a cruise to the coffee shop kinda guy.