i have been using obsidian since it exists, i’d say i use it once a month for like 10 minutes (local graph)
global graph seems more like a “pretty feature” (not useful), mine (10k notes):
i think local graph is useful in Publish for people not familiar with your workflow/structure
The following uses Google Translate
For local relationship graphs, it is my navigator, and for global graphs, it is my good helper:
Random roaming (with hover editor. idea from boninall:
安全验证 - 知乎)
Orphaned node
Intuitively discover possible duplicate nodes in the link
Find hierarchical defects (should I link to this node or its child nodes?)
The Graph view is great for just seeing what your biggest interests are, you can see areas grow over time, i find it interesting. The other day i was searching for notes with multiple tags and when the graph got filtered i had a nose around 
Well the reason that standard graph view is not useful is because it represents ideas as a network but doesn’t apply any network science metrics to them. It looks pretty but you can’t really get any insights from it because it’s just a visualization with no additional information or interpretation layer on top.
This is one of the reasons why I created a graph view plugin that’s actually based on network science.
It identifies the main topics (so you can get a good overview of the main clusters of ideas), identifies the gaps between them (so you can generate insights by bridging those gaps), and can be used to visualize only the files you choose, search results, or bookmark groups, which is great for getting an insight into a portion of your knowledge (the whole vault might be too big).
If you’d like to try it, you can get it on infranodus.com/obsidian-plugin
