Gearing?

I live in Bristol, which is quite hilly along the path I travel. I used the stock 48/16 for a few months which I kinda liked although can be hard. Tried 48/18 which was way too spinny for me, so I've just swapped it for a 17T, although haven't tried it yet.

shame this is being asked for cycling in Cambridge really, which is the polar opposite of Bristol in terms of the range in height above sea level between the highest and lowest points.