Global nav - how many items we want to add there?

I've seen we're adding a lot of items in the global nav (the navbar on the left-hand side of https://docs.gitlab.com/ee/). Should we aim to having absolutely all docs added there? I see the advantages and disadvantages of doing so.

👍 Advantages:

• Improved discoverability
• Consistent documentation structure (it's easy to see the file tree)
• All info there

👎 Disadvantages:

• Too much information
• Hard to find links
• Hard to navigate
• Harder to use
• Harder to maintain (considering the docs are added/removed to different projects)

@gl-docsteam thoughts? I'd also like to run this through an UXer to see what they recommend. :)

Brainstorming doc here: https://docs.google.com/document/d/1BJDu09kIASUYLftiqJCmqn-OFTdbwWSuZEeiLYqt1BQ/edit?usp=sharing

Here's the global nav, for context:

1st level	2nd level	3rd level