I think "A Silent Voice" is just what you need. It is not a series, but a film that lasts for a a little more than 2 hours. It is a very heart warming (and really sad) story. I'd also recommend you "The Ancient Magus Bride". I know you said you'd like something shorter, but I think this series isn't so long, it has two seasons and each has 12 eps. It is a very nice fantasy, and romance anime...I really enjojed it, and it is one of my favourites.