Not PoW, but rather a hybrid consensus algorithm (PoW + PoS). That would make a divide between network consensus and block production. Stakers will only earn rewards, but they won't be able to have a say over the future direction of the network. That would make ETH decentralized again. Or Vitalik and his team could introduce a new reputation-based consensus algorithm where users get to vote who gets to produce blocks and earn rewards (like DPoS, or even RDPoS (Randomized Delegated Proof of Stake) which is even better).

With Vitalik out of the picture, I doubt ETH will remain the "innovator" in the smart contracts space. You can see how Apple is not the same company it was once Steve Jobs died. Of course, someone else will take Vitalik's place in the future. But if the project doesn't solve its centralization issues beforehand, it will be game over for good. Who knows how ETH's market prices will react in the long term? Just my thoughts