I personally think a wide angle is the hardest to learn on. Personally, I don't shoot wide nearly as often as normal and a portrait lens. Some people are the other way around. I tend to prefer simpler images with fewer elements. As you can see in Micheal's first image, though, that can be done well with a very wide angle also. In 35mm I shoot only 35, 50 and 100 and it is plenty.