Good ideas but how will the prestige reward the player?
You will receive a prestige point and there would be a reward pool. Reward pool here means rewards outside of the game in form of HBD. The pool will distribute rewards (once a week/once a month) these are ballpark ideas. And you will receive a share from that pool depending on your share of the prestige points and activity status.
Things like you said that increases convenience will partly fund the devs directly and fund the savings pool. (Like let's say we as a game have 300 dollars as a reward pool sitting in HBD savings, we get 15% APR. We can distribute 5% of the APR as rewards, 5% to the devs and 5% to compound the reward pool.)
As the pie grows, it will benefit everyone playing the game. There will be no tokens that will be tradeable. All the Play2Earn stuff will happen with HBD. So people would not overly focus on the token prices or anything.
Game overall will focus more on the cooperation of players, so if someone pays to win in some sense it will not be detrimental to other players.
This is smart gaming. Use the sign up costs and stuff to grow the pool. If it's a Pokémon style game, having the ability to buy extra slots or limited time skins etc. Would boost the rewards. If a game the size of splinterlands did that, the reward pool would be nice and evenly distributed.