• Rank and progress rewards: I agree with what most people are saying about the progress rewards. I have spent money on the game, not as much as others, but I still have not reached cap level. Others have advised to save stamina theough the week in order to do well in the contests. However, by doing this, it is even harder to catch up to the ones that are maxed out. I would love to see more normal double drops, stamina, and soul stones (of player's choice) in the rewards. Diamonds are great to help lower level players.
• Skins: Personally I dont care about the skins. It makes no sense to spend anything on obataining skins. Now, if different skins came with different skills or attribute boosts? That would be something worth pursuing.
I dont really have anything else to offer, but I love the idea of creating a guild element as another person suggested. With the rewards distributed in porportion to the guild member's points earned.