This project is awesome, i was searching for several hours something like this, and is near for be perfect!, i hope you continue this.
I pray for this 3 options:
Thumbnails view
Screenshots available
Option for view the collection like genre
And i suggest this others:
Multiplayer number field
Some options for mark on the collection like "Game finished", "Wish or owned"
Make alliance with some page for use he data base like moby games.
Thank's for all
Saludos desde México!