Actually, dreamlands have slightly higher drop rate then the other zones. Each piece of gear have the same drop rate as AF do in the normal Dynamis zones. The exception is that there's 3 different that can drop. So the drop rate is a little bit lower then 3x what normal Dynamis drops.
The reason you don't get as many drops in Dreamlands is because of the 1h farming. Well, you can get it to 1 hour 45 min farming if you go straight for the boss.. what sucks about dreamlands is that you either chose to go for the boss or farm. If you go for the boss, you can't farm while going to the boss. So if you fail to the boss, you wasted a run. But if you chose to farm, you only have 1 hour to farm.
In Dynamis - Buburimu, it is possible to go straight for the boss, and thus have 1 hour 45 min to farm, but I don't think that's possible to do in Valkurm. Dunno about Qufim, though.