Why worry about that? I can't wait for all three lines to be complete so we can get "Big Book of Starships" "Big Book of Equipment" "Big Book of Aliens and Critters" etc. I'm tired of having to look through 50 books to find what i'm looking for.
Sounds like you could use an index !
Index's are useful, more so since I'm pretty sure they won't be doing big book of's.
A guy can dream though. I think almost every "book buyer" would buy one just by putting a few new items into each one. The fact that everything would be in the same place plus new content would be a fantastic deal for me.
I think there would be a lot of complaints about having to rebuy material they already own just to get access to a handful of new stuff.