The current classification hierarchies allow only one hierarchy per root. This constrains the hierarchies to be linear only. In most cases, particularly campaigns, I need many of the hierarchies to originate at the same root but have different classifications somewhere down the chain. For example, I want the campaign hierarchy to begin at the target product (laptop, camera etc.) and then I sometimes want to break it down by channel – like Paid Search, Banner Ads or at times I want to break it down by promotion type like Cashback, Discount. And thereafter do further breakups by creatives or target brand etc.
Classification hierarchies should multiple hierarchies with the same root. Also a tree like structure should be possible instead of just chains.