One of the things the new design has made much harder is the discovery of new subs; in the old reddit you could generally speaking find a list of related subreddits on the right side of the screen. Not anymore (sometimes they're buried in the wiki, but not always). It's a shame, because discovering new and interesting (and weird) topics was one of the best things about it. Also, to echo many users here, my usage of the site has dropped right down after the redesign. It's a shame because it was for many years one of my favourite places on the Internet.