As a Ex Professional Photographer, I have had some of my artwork used on books.
I pers like 1 & 3 however I think I have seen a similar photo to 3 on another book cover?
So 3 out
1 is ok for the Motorcyclist, to have the idea of Adventure.
2 shows the Tundra and indicates Camping & motorcycling.
overall 2 would be my choice if you are after a wider spectrum of readers.
We are the Pilgrims, Master, we shall go Always a little further: it may be beyond that last blue mountain barred with snow, Across that angry or that glimmering sea.