In my opinion, bikes of that era would be very easy for you to work on. No modern complexities. No parts that are hard to track down. Knock yourself out. If you want snob appeal, look for a brand name. If you want good looks, get one with good paint. If you want an easy project, get one that has everything and just needs a tune up. I would worry about the condition of the wheels primarily. If you can't true the original wheels, you might go down a rabbit hole of getting a replacement wheel that requires a cassette, then you will have to buy a cassette, and a new chain, new shifters, etc.