Bereft of the following ideas previous suggestion, I highly promote two additions to DS3. I believe they would make the game an instant classic and an undying, endless source of entertainment.
1. Repeatable and Randomized Dungeons.
This could be implemented as post game content and would feature varying combat and quest experiences that would be unpredictable. Upon completion of this type of dungeon, each player would receive rare equipment, deeds or upgrade components or other satisfying items.
2. Survival or Horde Mode.
Perhaps as a type of repeatable dungeon. The evolution of the current combat scenarios to bring a wealth of excitement and a sense of emergency to battles. Currently, outside of boss battles, most combat situations feature a few monsters that are defeated and you get to rest. Imagine, fighting for your life (and the world of Ehb) constantly intrenched in battle for longer durations than normal. Perhaps utilize a Gauntlet model: structures or monsters that would spawn enemies as long as they lived.
The above would help players achieve empowered abilities too.
I got most of my fun from Dungeon Siege from reloading areas to fight more monsters. I loved the Kairi Pass because it endlessly spawned creatures if the player kept running in a loop before completing the first quest!
What do you the rest of you think? I certainly advocate that Obsidian strongly consider the above.