I think your division -- ebook for breezier stuff, print for immersive stuff -- is much how other people do it, too; a lot of the ebook market is for quick-read genre stuff where people often want to rapidly read, say, an entire series by a favorite sci-fi, romance or fantasy author. (That's often how I work too.) Whereas students with textbooks -- where they really need to slowly ponder stuff -- vastly prefer print.