Hello,
please increase the droprate of AQ40 trash drops. BWL and Naxx trash drops for example are alot higher than the AQ40 trash drops. I would suggest increasing the drop rate from all AQ40 trash drops by 1-2 % on the mobs they can drop on. This would make them still rarer than BWL trash drops but not so low that you are extremly lucky to see 1 trash drop during an AQ40 run