Thanks again for all the excellent replies and info.
The heaters are already wired and installed, as as the On / Off switches, so I can't do major rework here. If there was a switch that could replace the simple toggles we have installed at structure, I would have used those.
My goal was to eliminate the need to have to work with the waterproof receptacle boxes to turn the heaters on/off, since its open/close mechanism isn't the simplest. I'd hoped to be able to use the Lutron software to do the on/off, and be able to set a rollback timeout. I didn't want yet another remote (the overhead patio structure already has its own remote, so I'd need it, this Pico or similar remote, and most likely my handheld). If there is no good option, its just easier to open and close the boxes and manually manage the switches.
@Imshea - I'm not sure which "Contactor/Relay" would work in the application, and can you explain what you mean by "near the breaker box"?