Another vote for the LED Lights.
We replaced all of ours with Pucks from Dream Lighting RV Interior Lights. They come in 3.5" & 4.5" Dia. In a choice of Soft White or Daylight White.
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1
They are not always available, as they were a couple of years ago when we did ours. I installed the 4.5" in place of the original 3.5". The lights are surface mount and thin.
So far, they've been reliable without generating large amounts of heat. The Daylight White really brightens up the interior. They are also dimmable.