This is something that's been brewing for a while, thinking of a way to present this, where to throw it, etc. I'm aware that Thief has Treasure Hunter traits, and things of that sort to enhance drop rates across the board, but there are certain... imbalances in the way areas like the Beastmen strongholds are handled.
Writing this while attempting to farm up a scroll of Carnage Elegy for my BRD, I realized that original beastmen strongholds (Castle Oztroja, Davoi, Beadeaux, Castle Zvahl) are still stuck on the original 16 minute respawn schedule, while later strongholds (Temple of Uggalepih, Sea Serpent Grotto, Quicksand Caves) are now on the newer, 5 minute respawn schedule, due to the addition of Grounds of Valor regimes to said areas.
The suggestion I have would be simple, add in Grounds Tomes, regimes and the like to the original beastmen strongholds (maybe with the missing craft skill torques?) and reduce the respawn timers on enemies in the affected areas. This would also help make these areas more popular, especially should you add in the missing crafting skill torques to these areas.