Found few pictures on Polygon showing new design for steam library. According to them, update will come this summer.
- Recently played & updated games will be shown on top of the page
- Custom tags will serve to sort out games easily
- Individual game page will contain all te main info about game, your progress, friends activity, updates...
Another interesting feature is steam events, which will allow you to be in touch with the most interesting events on your games:
- Double XP events
- Game updates