I gradually input thousands of flights from 40 years, and am very glad I did. The data base is very functional, so if you later wonder where you were on a given day, or how many times you've been to a given airport, it's easy to find. After inputting, I went through month by month to make sure that the data was reasonable, i.e. if I had one flight that was MCI-ORD, and then the next flight that same day was LAX-HNL, what's up with that?

The maps that you can buy are great. My advice is the bigger the better.