Nothing beats LED Christmas lights for safety and cost.
First, there is no comparison between the power drawn by incandescent lights and LED lights.
One thousand incandescent mini lights draw 408 watts. The same number of LED mini lights draw 69 watts, according to Christmas Lights Etc.
This can be a very important difference. For one thing, the LEDs are less likely to overload the typical household circuit. A 15-amp household circuit supports 1800 watts. Nearly every household circuit has several plug outlets running appliances or lights. Adding 400 watts to that circuit might trip the breakers.
Unlike incandescent bulbs, many strings of low-power LED lights can be daisy-chained with zero safety issues.
For example, suppose you need 300 feet of lights for the roof line. Traditional incandescent C9 & C7 lights come on 25-bulb, 25-foot strands. Only two strands can be safely connected end-to-end, so you would need six different plugs on different household circuits.
The same project with LEDs allows you to connect all the strings end-to-end into the same outlet. In fact, you could connect 40 strings of LEDs without a problem, according to Christmas Lights Etc.
In addition, LED lights:
* Use 75 percent less energy.
* Stay cool to the touch.
* Survive cold weather.
* Are more durable than incandescent and burn longer.
LEDs got a back reputation early on for being harsh. But newer designs offer choices between warm or bright white.
One drawback of LEDs? There is some evidence that blue LED lights make people feel sick or depressed.