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In my opinion, kulraj.org/author/admin/ is essential because it is the main listing for your blog. As the number of posts on your blog grows you might want to add categories back.  They can bring in a lot of traffic if the category names match a topic that people are searching for.  With a small number  of posts on your blog it is very easy to encounter duplicate content problems.  However, once you have a large number of posts then breaking them into a small number of category pages can become an important opportunity and a minimal duplicate content risk. If you do that I would limit the number of words that are displayed for each post.  I would also carefully choose the categories to match what people are searching for. I have a blog that does not have tags and does not have categories.  I do that to avoid duplicate content.  However, lots of my topics overlap and I have lots of linking from one blog post to another.  I also have some hand-built FAQ pages that link to my blog posts and other informative content.  These pages can bring in a lot of traffic.