UPSC syllabus analysis should be detailed enough to identify topics and themes, but not so detailed that you turn it into another set of notes. The goal is to understand the scope of each line in the syllabus and what UPSC expects from it.

A practical way to do this is by linking syllabus topics with PYQs and standard sources. If you can clearly map questions and concepts to syllabus keywords, your analysis is already sufficient.
Syllabus analysis is meant to give direction to preparation, not become a separate study task in itself.