1- Stats Page
Add ability to view in depth stats page of the last game played while in the Keep.
2- More Stats
Add more stats. Also, temp health damage should not factor into damage received stat, and least damage received should be highlighted instead of most.
3- Boss Maps
Boss maps are significantly more difficult, and therefore should have an added incentive. I was originally thinking a second chest. However, that seems like a bit much. So, perhaps something along the lines of additional ‘Dice’ drops? Making it somewhat more likely of getting an Emporer’s Coffer.
4- Inspect
In the Tab menu, add player’s power and equipped gear.
5- Friendly Fire
I like the idea of friendly fire, but trolls will always abuse it. As a Left 4 Dead veteran I am all too familiar with this issue. The ONLY way to counteract trolling in public games, while still leaving it in the game, is to cause the one who committed the friendly fire to receive the damage (not very realistic I know, but it gets the job done).
I had custom L4D2 servers that would cause the shooter to take the damage and in every single case the troll would join, end up downing themselves while trying to kill a teammate, curse a lot because of a failed troll, and then rage quit. Mission accomplished 
lol.