I know that when you come from a country with a huge coffee production it is hard to find lighter roasted coffee. When the coffee is average and below average, you should roast it darker to cover the flaws as you have said. Lighter coffee is more expensive and it is clear why. Mass producers prefer bigger crops at the cost of lower quality beans. Here in the supermarkets the coffee that can be found is medium to dark roasted too. We are lucky to live in a world where specialty coffee enters relatively fast, so I have no issues in finding a tasty, light I medium roasted coffee beans.