New to me, but very much my line of interest. A casual glance shows one area of omission: Ornithopters; this is not a criticism, just an observation! Long regarded as an impossibility and therefore not "aircraft", with modern materials and engineering they have at last flown so I feel their ancestors do have historical merit. Certainly London's Science Museum has a few bits of Frost's Ornithopter on display; slight bias on my part because we are related!
In my experience a lot of people seem to think that there were no working aircraft before the Wright Brothers, and I think the full history of flight is particularly interesting when you study the pioneering work before their time.
I feel a purchase is imminent!