I kept a 47t chainring on the bike (I like prime numbers for track bikes) and usually used a 17t sprocket for general street and road use. I could climb in that sprinting short hills, or biting the bullet on longer ones, and got pretty adept at fast descents.

If I knew I was headed for a fast flat course on open road, I go down to 16t, and sometimes even 15t but I really had to be feeling my oats for that.

I also have a 51t chainring used it once in a while, but tended to get lazy and not bother changing rings. In fact it took a lot for me to switch to the 16t in back, so the bike was 47/17 99% of the time.