How do I update 70's cabinet doors?

You have the same problem as me, only your cabinets are in a much better shape. I have just posted a question on here that you might like to look at and peruse the answers.

you can remove those pulls and fill the holes with wood filler, let dry and sand smooth.

They need to be strip, holes fixed with wood putty ,sanded, painted again. Then put new hardware on them

Somebody suggested I decoupage my cabinet doors which has let my imagination run wild. I am about to do something along these lines with my laundry room doors (same style) and just see what happens.

When I have eaten my doughnut, I am going to degrease the doors then play around with paper patterns dipped in cold tea to look old. Maybe handwriting, old postcards or brighter patterns of Paris, scenery or animals/birds. I have a lot of designer paper to hand. And ideas are abounding.

I had almost exactly these doors many years ago. Fill the holes with wood putty and sand. You may have to fill, let dry, lightly sand and fill again. Sometimes wood filler shrinks into the hole and you need to add a little more. Be sure to scrape the putty as smooth as possible when you fill the holes so that you don't have much to sand. You do not need to strip the cabinets if the paint is in fairly good condition. If you have rough spots or loose or uneven paint, just lightly sand until smooth. Use a liquid degreaser/deglosser and follow the directions exactly. This will make the surface tacky and clean and help the primer adhere.Here is where I am going to suggest something that differs from most people: please use oil based primer. I know that it is harder to use and requires tougher clean up, but it will make your paint job last so much longer. Then used the highest quality paint you can afford-latex or oil. With all the effort it takes to paint cabinets, don't skimp on the prep.