The reward structure is still way too top-heavy and doesn't really give a proper incentive for players to level up. I would even it out so the average players get more rewards instead of a handful of players who are just the best and also own the hero to get all the prizes.
What I would do is start out league 1 where maybe 30% of players get a reward, in League 2 make it 40%, League 3 50%, League 4 60%, ... and so on while making the gap between rewards smaller and more gradual so each spot gives a bit more. I would also give players 1 Free Test run just to see how well they manage to do and if they want to play for the leaderboard they have to pay to play with tickets so there is actually a sustainable revenue model for the rewards to keep going.
That said, I still enjoy my daily run of Soulkeep even though at best I'm getting 3-16 SPS while regularly I end outside of the money. Not owning the hero feels like a major handicap.
As for the Reward Structure - I am not sure what's best.
As for Celene - she is absolutely critical and Owning or Renting her is a must for high level play