I think the ETH will not convert to PoS in the next few years. It has supported a big industry and the hard forked was supported by miners.
The next few years? The Ethereum development team has already said that they will switch to Casper in 9 months. So expect another fork. Some speculators even say we may even have 3 or 4 Ethereums next year due to more forks thanks to Vitalik.
That could be right. So there will another pure PoW Ethereum. So maybe it is safer to stay in the PoW Ethereum.
Maybe. But that would only mean that Vitalik does not have full support from the community now. The POW Ethereum will be not in the control of Vitalik and the Ethereum foundation.
I heard that the Ethereum PoW is much safer. The number of Ethereums owned by the big holders are too high from the ICO. We need to use the PoW to reduce their proportion.
The thing that can make Ethereum Classic stand out is staying PoW. Ethereum Fork can't stay PoW, they are already committed to hard forking again to go PoS. This is predicted to be a disaster by a lot of people because of what you said. It will be a centralized mess of whales deciding what's up without other forces to create a valance with just like what happens with PoW.
So there will be three Ethereum next year. The Ethereum Classic, The Ethereum PoS and the Ethrereum PoW. There will be more in the future.
The Etheruem is a good platform to do forks. So people will love it and develop based on the Etheruem platform.