I am good in theoretical portion so what I choose C.A. or C.S.
Hey Harsh! Theory is actually come from good understanding and thinking and it demand for both CA and CS .Many students focus on covering their syllabus only as they not focus to think much and cover only syllabus
But as you said you are good in theoretical portion you can go company secretary .you have to really make it interesting for you while pursuing and along with your syllabus you have to cover your learning capacity.
You have to think more about the subjects and learn all the concepts very well for the it demand a serious thinking about incidence happend in company, issue of black money , window dressing etc in company.
Your attitude towards your study really matters government and finance ministry also go through their thinking process for the tax reform, budgetry control and after the completion of your course, your practical knowledge demand more .
You have to be confident and good thinker for the progress of any company and you will also share your knowledge with others in future.
My best wishes to you dear!