What features do you want in a anime/movie tracker?

If you were using a movie/anime tracking website, what features would you actually want it to have?

I'm interested in hearing what people find useful in a tracker, especially features that are missing or could be improved in existing ones.

It can be anything from tracking, collections, ratings, watch history, social/friends features, discovery, importing data from other trackers, or anything else you think would make a tracker better.

What would make you actually want to use one regularly?