One early fantasy series that I read was The Belgariad by David Eddings. Here are the covers as they looked on the series when I had it.
As you can see, the titles are all on theme by being about chess (“pawn,” “queen,” “gambit,” etc.). The covers are all similar, but each cover has a slightly different color scheme to vary your reading experience: mustard, green, rust, blue (harder to see in this image), grey. After all, you’re going to be looking at that cover for a while, as long as you are reading the book and carrying it around. It will form part of the visual landscape of your life. Also, and this isn’t obvious unless you’ve read the series, the color and general look of each cover matches the country to which the adventurers travel in that volume.
Last week, I unveiled my draft for the cover of my book The Long Guest. With the help of blog commenters, the font that we settled on for the title (at least for now) was Goblin Hand:
Now here is the draft for the second book in the series. I’ve kept the font and general title layout, but the color scheme is colder because, after all, we are going to Alaska.