...Most photocell manufacturers have upgraded their products and will put a small "LED" logo on their box to indicate that is OK to use...
Photocells are somewhat of a different issue. Some cheap old style photocells would flicker rapidly at dawn and dusk. It wouldn't be an issue for incandescent bulbs, but would eat fluorescent lamps rapidly. LED rated models have electronics that snap them on and stay that way for the duration of the day.
As I pointed out above, the switch in question has a horsepower rating for motor loads. That certainly accounts for inrush current and bad power factor, and if you stick to that number you should be safe with an LED load. Note that in this case, the LED switch rating is only 12% of the tungsten rating.
I'd guess that for a one-season holiday display, the one switch option would probably last just fine. But for a permanent installation, I'd expect it to live a relatively short life. If you plan to pack this up and re-use it year after year, you'll likely have less headaches splitting the load or going with a bigger switch.
You don't necessarily need a second timer. You could use the output from your timer to drive a 120V coil relay. This relay for example:
https://www.amazon.com/dp/B0030G8SC8/?tag=atomicindus08-20
has a 2.0HP rating on the NO contacts, which could easily switch your load forever without strain, and without a second timer.