Some time ago I created a web-based app to manage my subreddits. The thought was, every subreddit have to be in a multireddit, maybe in more than one; and there are multireddits (NSFW in my case) that can contain subreddits I am not subscribed to. I needed a simple to use interface to enforce those rules, and Reddit’s interface is pretty much unusable for this task.
There are a lot of shortcomings: it doesn’t support batch operations in any form, interface is barely usable, but ohwell. I am not saying this is going to change anytime soon, but who knows?