As I can understand the most close to ETH is ETC and Zcash.
I do not see ETC as a good coin neither to mine or invest.
What about Zcash? This coin will also benefit from ETH switching to PoS?
What about the price?
True I heared there is a mining boom in countries with cheap electricity mostly eastern europe and Russia which start to mine ETH and Zcash as crazy.
They pay almost double price for GPUs. And there are still not too much GPUs for them at market.