I made a quick decision and picked up the sigma 28/1.8 off the marketplace. I figured since I take a lot of indoor photos, and the 50/1.4 sometimes isn't wide enough, the 28/1.8 should suit my particular needs.
I liked the idea of holding on to it, at least for a few months to see if it really gets neglected.
In looking for a new lens, I did what many/most of you have probably done. That is, write down what you have and what lenses you want to cover the wide spectrum of focal ranges. All I see are $$$ and that I have a long way to go