Lock in one writer to a cheap, lengthy contract, and let them go to town. Like how every Warcraft book had to be Knaak gushing about his pet character.
Even WOW got like 2-4 writers, Golden and Knaak wrote the most of them. Even Golden's WOW works are much weaker before the great SW novels(Thrawn Trilogy, RotS, Plagueis). However the quality of TOR novels are just horrible.