Thanks!

I use a tool I’ve been working on lately: <a href="https://tools.wmflabs.org/flickrdash/" rel="noreferrer nofollow">tools.wmflabs.org/flickrdash/</a> — it makes it quicker to tag the Flickr photo and add Commons categories at the same time (it uses the ‘commons category’ property).

I’m currently trying an experiment with a category page: <a href="https://commons.wikimedia.org/wiki/Category:Cossack_Cemetery" rel="noreferrer nofollow">commons.wikimedia.org/wiki/Category:Cossack_Cemetery</a> (not sure if Commons likes that sort of layout though!).