i, too, use a 35/1.4 (pre-asph with the Epson, asph with the Leica) most of the time and have been using it for nearly two years on mostly cropped sensors (R-D1, M8). i love limiting myself to a vision i know.
that said, i am dying to use it FF after playing with it on film, knowing i'd be most comfortable using it as it should be used... but still, i adapted, and learned to use my feet when possible, only putting a second lens (Noctilux) in my purse if i knew i was going to be out after dark.
i have other lenses and love to play with them, sometimes taking them for a walk or to a bar. it's fun to challenge myself now and again, to see things differently, and keep me from becoming complacent.
the reason i asked if people primarily use one lens is because, i think, most do. we become comfortable and at home with it, so that the camera and lens become an extension of ourselves.
but very few of us completely rule out other lenses and that is good to!
i'd suggest the OP trying to limit himself to one lens for a shorter period of time and/or switching focal lengths weekly (monthly?), round robin, to really get to know each lens... or maybe use one focal length for 95% of the time as many of us naturally do...
but if he really wants to do this one lens for six months, however, hearing what other people shoot and why might help him make up his mind on what to choose.