ETH and others aren't CPU heavy but rather memory heavy (please read ETH design paper). So any ASIC for ETH has to have TONS of fast memory. You can still make ASIC for these algorithms but they won't give you such tremendous advantages over GPUs as for CPU-heavy Bitcoin.
However, Chinese guys can kill ETH and others just by concentrating their money on the Bitcoin (so nobody will want to buy ETH at the first place).

OTOH, this all madness is a bubble / Ponzi scheme. So I think it is going to crash sooner rather than later. I wouldn't invest anymore at this point; just make sure you cover the equipment/electricity that you already bought to at least break even. To get rich on the criptocurrencies you should've invested big $$$ back in 2010.

Disclaimer: This is just my opinion. I am not your financial adviser / lawyer / rabbi / etc.