@Sirrian When you have that meeting, may I suggest you revisit this thread whereupon I suggested how to expand Arena with two more Arena-type games.
You could have them unlock at higher Hero levels if you like now that the 1000-hero rank has been lifted. Arena, as you’ve stated, is suitable for newcomers whereas the other two I suggested could be for higher ranks. Perhaps, they must reach hero level 400 for one of them and hero level 800 for the other just to keep from giving too many goodies away at the expense of the game.
I do agree that if a player does win at harder difficulty, that bonus should apply to keys and trophies as well. I don’t know about adding glory as a reward but I know Event, VIP, and Gem keys could be added as rewards with the other two Arena-like modes. The fact of the matter is every player will need to save a lot of copies of the same troop to ascend them. Not every player will belong to a great guild, or play as much as they like to, or spend more than they need to. But if the game provides much variety in PvE with rewards to match, those players will be around for the long run. And during that run, tip you guys along the way. Quite generously too if I may add. 