Thanks, everyone, for all of the thoughtful and/or humorous replies.
I placed an order for a DFA 50/2.8 last night - given that I was buying a lens simply for the sake of doing so, its price and capability allow me scratch my itch with something I can enjoy for not much money.
I was tempted a bit by the DFA 15-30, but - as I said above - I seem to use lenses with this FOV sparingly, and the size and weight of the 15-30 would contribute to my tendency to leave it in the cabinet. Also, I have a sizable collection of DA lenses that includes the FE and others that allow me access a wide FOV with my K-3 in those rare times I feel the need to do so. Having said this, should Pentax introduce a FF wide angle zoom smaller, slower and cheaper than the 15-30, I admit I'd probably pull the trigger on one.
Jer