I don't agree with staking requirements for Soulkeep, actually or for Splinterlands. If I spend thousands of dollars on card packs I've got a "stake" in the game. Requiring players to buy/rent cards to play as well as requiring them to buy/rent & stake a token to earn rewards is just convoluted and overly complicated. Imo the swap from earning DEC to staked SPS in Splinterlands was one of the factors contributing to its current state and I honestly believe is a limiting factor on its growth potential.
It may not be popular but I think maybe a KYC system might be considered. Perhaps with players allowed a few linked multi-accounts(whatever is deemed fair by the community).
Other than multi-accounts the biggest issue atm is an image thing. Plain and simple the rewards "look" to much atm because they are meant to be shared out across thousands of players. Less than 250 accounts played one night this weekend...total across all leagues! 132 of those got a payout. The rewards are going to be outsized regardless of staking until more people regularly play and the rewards get diluted amongst them.