Odd that I've only had the Sony cameras for a short time but I have already acquired two 50mm lenses, one 35mm lens and one 30mm lens, along with a zoom that also covers the 50mm focal length as well as the 35mm focal length. I don't have anything wider than a 24mm (35 equivalent) and yet I don't feel nearly as naked as I did when I didn't have the middle of the optical range well covered. (This was written a while ago. I'm editing: I've added a Sigma 10-20mm lens to round out the wide end.)
All of my current photography happens between 16mm and 200mm. The lenses are used on APS-C camera bodies so the range actually covers 24mm to 300 mm, in old school speak. But no matter what I intend or what I head out the door with the images that make me happy are always in that narrow band of focal lengths that emulate what I learned on with that old Canon TX film camera and its bulky but stalwart 50mm 1.8.
When I shot everything with the Canon 5Dmk2 I ended up collecting at least five optics in the "normal" range, including: a 50mm Zeiss f1.4, a Nikon 50mm 1.2, a Canon 50mm 1.8, Canon 50mm 2.5 macro and a converted 60mm Leica R macro. I guess it's a bit of an obsession. But one that makes sense. We're seduced by candy and sexy super models and loud music but we spend time with nutritious food, approachable girlfriends and soft music in our ongoing lives. We think we love the sparkle but we stay pretty firmly in the comfort zones. It's no different with optics.
From 35mm to 85mm or even 135mm we feel safe and sound. We're excited to play with a 15mm wide angle but we soon tire of its uncomfortable novelty effects. We marvel at some shots taken with an 800 mm lens wide open but after a very short while we long for the context that comes from seeing more of a scene. And seeing more of it in focus.
I've owned the high speed, high priced normals and I've owned the cheapos and I'm here to tell you that, unless you spring for something esoteric like a Leica 50mm 1.4 Aspheric, you're not going to notice a heck of a lot of difference between the lenses once you hit 2.8 or so. You know, the range we mostly shot at or above.