For instance, theodicy. There are dozens of books on this subject, and many are considered classics or "must haves" for those studying the topic. Not so many can be found in Logos. While I understand the concept of PrePub, I really think that at times FL shoots itself in the foot with their slavish adherence to this approach. It may be scary, but I think an "If you publish it, they will buy" approach would pay off. There are a variety of ways FL could go about deciding which titles to carry and include in such collections. A search for "best books on theodicy" will provide many lists; taking the most often cited resources from the bibliographies of books in these lists would be a good idea; and asking/getting user input would help.
I suggested this elsewhere (re: the DeGruyter offering that didn't take off), but rather than bundle 20-40 such titles into one expensive bundle (even though I prefer such collections for the deep discounts), it would be better to offer a few smaller bundles that folks can afford. Also, offering a pick-and-choose menu of titles with a "3 from menu A & 2 from menu B" vibe that allows customers to shape their own bundles would probably entice many buyers.
KEY to pulling this off is GETTING THE TITLES PUBLISHED IN LOGOS, so that the bundles can be offered. On some level, FL probably already does something like what I'm suggesting, but the vast number of classic and critically important titles not currently available in Logos format remains significant. My Amazon wishlist has many dozens if not hundreds of titles that aren't available in Logos. Having something like "comprehensive subject matter collections" would attract a lot of interest, I suspect.
