I saw your post link on Reddit- very helpful. I'm still learning about the bots, and contests - things I wish I would've researched more earlier. Another thing I would recommend is: don't forget to explore and use different tags that aren't in the main list.

From posts in #food I found users using #foodphotography, #dailyfoodphotography, and other interesting tags. Each one you encounter you may find a niche that you can fill ,or new and interesting users that share your interests.