I wonder if an editor would be happy with him remaining so anonymous today, although the author of the Puppy Place books has successfully done the same. I think it would be harder for someone newer.
We love E. Brown in this house. My kids reread him periodically. We even baked brownies form the mystery cookbook. (10 stories all revolving around food and with ten recipes, one per story.)
We also love Sally. She even solves a mystery in one of the books.