Nice review, thanks!
I respectfully refute this statement, both that bards must be entertainers, and that the spirit college cannot be an entertainer.
I wish I had this book when we played CoS. "Spiritualist" was my concept and I hesitated between the bard and warlock for my class. Ended-up going charlatan lore bard because I didn't find a patron that I liked (for that concept), and because street fortune telling and bonaventure was his form of artistic performance in a totally cliché "Mme Olga will tell your fortune!" like in the early 20th century grand opera variety shows. Anything that would end-up on a stage or in a cabaret, or during fairs or in tourist traps, is entertainment IMO.