ive seen headlights fail and replaced the switch temporarily with a pull switch from a 122, its just a switch. You can check it with a meter to see if it is working or bunned. when you turn the lights off and back on you are also opening and closing the contacts inside the headlight relay. they may be blackened and intermittent. if you pull the relay maybe you can pop the cover and pull some 400 grit wet or dry sandpaper through the contacts to get it going until you get a new one. headlights are important so I'd replace it if you have issues. the dash light dimmer is probably a variable resistor , you could jump it and get full brightness or replace it If it still kind of works i'd see if you can measure the ohms resistance with it unhooked and you can likely replace that with another variable resistor or even use a switch to engage a resistor for half or part brightness instead. If you hooked it so you had a switch and half brightness or full brightness that might be good enough, who needs the variable feature really? you might try spraying the switch with de-oxit to see if that revives it.
also check the buttons on the door, they often go flakey causing the interior light not to come on when you open the door but the dome light should still work in the always on position. if someone has been changing the radio or the heater blower or pulled the tranny then sometimes the little lights and things get left unplugged. Its really cool to get them all going at once, not uncommon some don't work.
if your fuses are going oxidised it's worth the time to unhook the battery, pull all the fuses and clean the fuse holders with a brush and contact cleaner then refit new fuses. sometimes the fuses get corroded or sometimes they can break with out appearing blown.. you can check each one with a meter to make sure you have continuity through each fuse. if the fuse holders get hot from a bad contact they can use their springiness, see if they are weak, sometimes you can re-form them a little to get them to hold the fuse with better tension. .
if you have fingers the size of a three year old that's perfect for pulling the fuses. If not get some spares, I always seem to drop them and they go down under the floor carpets never to be found until you have to pull all that apart so good to have a few spares, or think ahead and lay a cloth down to catch them.