As quoted by UPSC in its notification:
” The nature and standard of questions in the General Studies papers of the UPSC Civil Service Main Examination will be such that a well-educated person will be able to answer them without any specialised study. The questions will be such as to test a candidate’s general awareness of a variety of subjects, which will have relevance for a career in Civil Services.
The questions are likely to test the candidate’s basic understanding of all relevant issues, and ability to analyze, and take a view on conflicting socio-economic goals, objectives and demands. The candidates must give relevant, meaningful and succinct answers to the questions asked by the UPSC in the Civil Services Main Examination”.
Whenever you have a doubt on how to prepare for mains or how “MUCH” should I study for mains, please read the above quote. UPSC is clearly telling you the demands of the exam and the grounds on which the questions will be framed. So Don’t fall prey into chasing content and draw the limits to your content on the basis of the above quote.
It is advisable to take a print out of this quote and stick it in your study room as it acts as a constant reminder to not overdo on the content part of your preparation. Good Luck 🙂