It’s not a good idea to mix LED and incandescent Christmas lights if you can avoid it. LEDs and incandescents can have significantly different electrical current needs. This difference can lead to a higher risk of problems and failure for both light strands. When possible, switch all your lights over to one kind or the other for the best results. Do not connect the different types of light strings to each other, and avoid linking them to the same circuit. 

Baking soda is an effective fire reduction method. However, flour and baking powder are very dangerous around flames. Flour is flammable and it can also conduct electricity. The combination can cause serious injury from electrical shock and worsen the situation by adding fuel to the fire. Baking powder is also not an option as it's also highly flammable. 

While not always necessary, wiring your circuit breaker in a certain way can ease both the installation process and use afterward. For starters, you’ll need to install the electrical panel so that the main service knockout aligns with the cable conduit. If they aren’t aligned, you may not have sufficient working space to finish running the wires. Using cable trays, on the other hand, gives you a bit more freedom to and flexibility in where and which direction you install the wires. At the end of the day, the power flow will be the same whether the cords run up or down.

For a 200-amp underground service, you need a minimum of #2/0 American Wire Gauge (AWG) copper or #4/0 AWG aluminum or copper-clad wire. Don’t forget that, at minimum, you’ll need to use a 1 1/2-inch schedule 40 or 80 PVC conduit to successfully run a 200-amp underground service.