Current navigation patterns for large-scale websites move away from hierarchical structures and towards taxonomy driven systems. The Resource content type can be a first step in this direction.
Over time, any hierarchical structure tends to grow both horizontally and vertically - and the tree grows into a jungle. To avoid this growth, we recommend a content strategy that moves away from a hierarchical structure and towards data-driven content.
To move from pages to data you need a clear strategy for what goes where, and why. Take time to sort your content into resource types and topics. Think about pre-filling your 'tag' taxonomy with useful topics that help your users to find content.
This sample node is a node of the content type Resource.