To accomplish the objectives of promoting the enjoyment of the Signum community, making some money to support Signum U., and raising awareness of Signum U, I suggest the following Merch principals might be useful:
1. Merch should generally have two logos. One logo referencing a book studied. One logo being the Signum U logo (Or, perhaps the Mythgard Academy logo - depending on the branding strategy). Over the logo perhaps text, "Study the Story!". Under the logo, "At Signum University!"
2. The logo representing the Book should ideally be clear and iconic. Suggestions for TLOTR (some of these might have to be re-worked to avoid copyright problems): It seems the most common LOTR icons are: The white tree of Gondor. The Ring, with it's inscription in tengwar. The inscription on it's own. All of these might be utilized in some form. Also, blast from the past, in the early days of LOTR fandom, "Frodo Lives" was a very common fan merch message. This might be updated and made more intriguing as, "Frodo lives! - Or does he?" accompanied by some LOTR image (perhaps an Elvish ship heading for Valinor). Other possibilities: a graphic of Sam looking at the star of Elendil with the message, "Hope!"; How about a graphic of 'Seven Stars and Seven Stones, and one White Tree, with the message over, "Seven stars and seven stones and one White Tree", and the message under, "Gondor Forever!"; How about a mass of horsemen with spears on a ridge, with the text. "Ride now, ride now! Ride on Rohirrim!" (the image could also be charging cavalry, loosely inspired by Elizabeth Thompson's painting, 'Scotland Forever') ; Or, the image of a white horse (like the one on a hillside in England) with the text, "Faithful servant. Swift Snowmane."; A graphic of mountains, with the text, "Misty Mountains - Adventure Awaits!".
3. For Narnia - The head of a lion, with the text, "Aslan - Not a tame lion!"
4. For the Wizard of Earthsea - A graphic of a small sailboat with a lone sailor on a wide ocean. Text, "Fill your sails. Raise the mage wind!"
I'm sure others can come up with plenty of other ideas, and ideas for all the other books which the Mythgard Academy has studied.
This sort of merch strategy would clearly identify a popular book, (ideally in an arresting or intriguing way), and link that to Signum University (or to the Mythgard Academy). It would use the better known brand of popular books with plenty of fans, to promote brand awareness for Signum. It would graphically explain (at least some of) the purpose of Signum U, in a way that the Signum logo alone does not ("Oh, there's a University where I can study the sort of books I love?") I think that this might lead to a clearer and more consistent merchandising and branding strategy for Signum?