There just isn't room here for me to discuss this. However, tinkering is half the fun, and making a semi-cool bike into a cool bike is fun.
My guess is that if you buy one to fix up, and it's not a basket case, you'll find yourself buying another one. It just sort of happens.
When you run out of room in your storage area, then you'll know.
+1 to a decent used modern bike, unless you're like most of us here, and we like to work on the older stuff.
It's not hard. If I can do it, you can do it.