I challenge you to mention a book about the CB750 I don't have...
The "Classic Honda Motorcycle Buyer's guide is not worth from a CB750 perspective. It covers all the classic Honda models, so the CB750 is deal with briefly.
I have the "Original Honda", the Haycock book, the Duckworth book, the "Honda 500 GP wins", the Clymer, Haynes, 2 original shop manuals, three part manuals, the Chilton's Honda fours, and even some other edited in German by Motorbuch Verlag. One of them is comparable with the Wyatt's, in text and pictures qualities, but it's in German, so if you are good with the pictures then it can be a nice addition.
Apart from that, I have the "Honda CB750 Gold Portfolio", that is a collection of period articles. From them, many I have also in the original magazines. I bought the "Cycle" and "Cycle guide" magazines that covered the CB750 launch. Apart from that, some other magazines that cover the F1, F2, K3, you name it. The CB750 win at Daytona. And, easy for me but a collector item, some spanish magazines dealing with the CB750.
And, of course, brochures. I have the K1 brochure, the K1 german brochure, the british brochure, the international version brochure, the F1 brochure, the DOHC, the Seven Fifty, the CB400F, the CB500, as well as magazine ads: "Sooner or later, you know Honda would do it". My favourite is a german ad with a nice woman in the picture. "Freiheit" -freedom-. in black and white. I will probably frame it.
My actual avatar is from a Honda CB750 model that I bought from Japan. There is a 10 pence coin besides so you can compare the size.
My wife says I'm obsessed..