[lkbm]

Oh man, Literature Map looks really great for finding recs.

That said, I do think book-level might be much more valuable. My first thought for this was Night in the Lonesome October by Roger Zelazny. I haven't read anything else by him yet because my brother informs me his other stuff is entirely different. Looking at Goodreads, I think that qualifies as far from his biggest hit. Is it "more profound?"? Doubtful, but seems likely that you shouldn't group it with his others. I want recommendations based on the book I like, not the author I mostly might-not.

A better example might be how Stephenie Meyer wrote the extremely popular Twilight books, and also The Host which is much less well-known, and better in many respects. Probably qualifies as more profound, too—it's told from the perspective of a parasitic alien. Picture the Yeerks from Animorphs if you read those.)