I suggested this in another thread about improving TH… if matching vaults were possible, and the result were fixed, like say a vault key for a three vault match, and an epic one for a four/five vault match… those potential rewards would definitely incentivize TH, imho.
In terms of TH rewards, in the mini game mode’s current state, if one is somewhat efficient/proficient at creating vaults in TH, one may be surprised at what an acoount built solely on Treasure Hunt could look like. 
