I think , for me, it is what I see my hand drifting towards when I go out. However, I am trying to make myself swap from camera to camera so I get to use all of them as the weeks pass. That means I have to keep a list of what I have been shooting so I don't leave one out. I just recently got a Nikon F-100 so I will slip it into the rotation soon.
That is a great way to approach things! I do the same thing too! I force myself to try different focal lengths to stay out of my comfort zone. However, if I were to pick a second favorite lens right now, it is a 135mm prime. On full frame, the compression looks awesome and is a great pairing with the 40mm wide lenses.
