The key to making good fish and chips is the in the four main ingredients;
1. Excellent quality potatoes
2. Excellent quality fish
3. A delicious and golden batter
4. Excellent quality cooking oil (changed regularly)
Many fish and chip shops try to skimp on everything, and they end up selling a really shitty (and soggy) product. Having pride in your offerings will generate a large and loyal customer base (and word of mouth advertising).
I have eaten fish and chips all over the world, and the best fish and chips I have had are in Toronto (funnily enough).
Here is a link to have a look;
http://www.chippys.ca/