Thanks for the suggestions!

I too, only run in the summer and let the pool freeze in the winter.
Getting a 2-speed pump sounds like a option. I just don't like changing out my almost still new 1hp pump.

I think I may look at getting a smaller pump, say 1/2 to 3/4hp and install it in parallel with a couple of check valves. This should be cheaper than a new fancy 2 speed. I can then power up each of the pumps I want through a timer and have the benefit of a back-up pump. I'll just have to install the proper switches and wiring so as to not have both pumps come on at the same time on the same fused circuit.

It would be great to have the system operate automatically based on the real demand. Are there any devices out there that can automate the need for turning on the salt water generator and pump? I'm imagining that there can be a remote, hopefully wireless, sensor you can drop into the pool that reads the chlorine level and maybe other parameters such as temperature. A reciever/controller can then trigger the pump and clorine generator to come on only as needed.