Both ideas are very good, but both of them are attention, time-consuming and could lead to crushing of the game experience.
And I say that, judging from my own game experience.
Your first idea means that:
Players will actually have to SIT and THINK about creating incentives for others, in order to have their quests completed. Having a competition for quest writers that has been running almost 9 months... Only handful of people made some effort to write something, despite the MASSIVE quantities of Diamonds I throw at them. I seriously doubt that there will be enough players who will want to do stuff that, according to them, needs to be done by the IH Team. So, there will be 2 months of enthusiasm and then the players quest screen will be empty.
Your second idea means that:
I will create 10 accounts, develop them enough to be bankers and I will start multiplying my gold by giving it to them for an interest. This is just the first scheme that comes immediately to my mind. And this scheme only will crush the game economics. And I'm sure players will think of another 1000 schemes which I am too lazy to brainstorm at the moment.
So...
Your ideas are good, my friend... But in a perfect virtual world. Not in Ayarr Empire.