Hi all,
Thank you to everyone for their contributions. It seems there are lots of solutions out there. I'm trying to come up with a simplistic method that could be applied generally.
Concerning the use of NTC thermistors as a one-component solution: my biggest concern is the temperature of the thermistor during steady-state operation. Is this a valid concern? Should the device be thermally insulated?
Lately I've been thinking of a method that has a small part count. What about a small NTC thermistor in series with the coil of a '120 volt' relay - one that uses mains voltages to operate the coil. This would create a time delay on the relay closing after mains voltage is applied. Once closed, the relay could be looped back on itself so that it pulls its own coil up to main levels thus latching it. During the delay time, an alternate path could be provided - this would be the soft start path - for the current. The alternate path could be another NTC thermistor, or power resistor, or even an incandescent lamp was a thought that came to mind.
As an aside, an incandescent lamp might make a good power resistor, as it is already setup to handle heat dissipation.
Jim