Mr Pip
Make sure that the guitar your cuz gave you isnt some classic that might should be left stock. If not, switching to hummers isnt to big a deal. But my suggestion is to play the single coils for a while and explore their tone. you might find you like it. If not humbuckers put in a strat with 3 singles could require some routing. This could be risky and destroy what tone you have. But if the guitar isn't to good anyway; go ahead and experiment with different components. Not only is it fun but you might just create a masterpiece. If the body looks a little rough, leave it alone. Thats called character and it makes it look like you been playin awhile. Or if you're looking for that funky look, cover it with stickers. Refinishing a guitar with spray paint usually looks like s.... For a natural classy look, sand it down to the bare wood and let it mellow with sweat and oil from your hands.
Guitars save lives!!!
"When the power of love overcomes the love of power;we will know peace" J. Hendrix