By setting an upper limit on the computing power of each miner, it is possible to mine on a mobile phone without consuming too much computing power.
Sounds terrible. First of all, why would you want to intervene in miners' belongings? What's the problem with one individual owning more than 100 others do? Secondly, why do you find this more decentralized? To forbid someone from using multiple faces, KYC must be implemented; and even that way, you can't be sure the mechanism won't be violated. Thirdly, how will the minting work?
Yet, another well intended idea which would have opposite results.