I believe professions are the #1 thing that sell RM books. So it makes complete sense to do the various realm companion books, each with a few new professions. Personally I think each realm book should have at least 1 Pure, 1 Semi, and 1 Hybrid from each of the other realms (total of 4). Which means at least 16 new base lists and it would be nice to see some expansion on Open and Closed lists in each so long as they are not too redundant or frivolous. Maybe throw in some "Cantrip" style lists if a more generic "spell users companion" isn't done (i.e. I would think the three realm companions would make that book unneeded).