At one of my teaching gigs, they use Blackboard, which is completely awful aside from one saving feature. There's a plugin called Crocodoc (though now apparently called "Box View"), which is totally awesome. I can grade students' Word documents right inside Blackboard without having to download them, make inline comments and then upload them again. It allows inline comments, highlighting, etc.
Is there anything similar to this for Moodle. I did a forum search and found exactly 1 post that mentioned this plugin being used in Blackboard & Canvas. I'm sure having a feature like this would bring a lot more people on board the Moodle train.
Here's a picture of it in action: