My attitude is if I trust Komodo/SuperNET to buy KMD and SN assets, then I would trust proxy ETH/XMR/ERC20 tokens issued by Komodo/SuperNET to the same degree, which is infinitely higher than either bittrex and poloniex, especially after they've gotten so hairy chested demanding KYC selfies with piddley withdrawal limits etc
I can't trade ETH/XMR anymore now that bittrex/poloniex have become unusable.
afaik anyone is free to create an asset chain on BaterDEX, so if it's possible to create proxy tokens for ETH and erc20 coins we should expect them eventually.
jl777 has enough on his plate already, so an opportunity for others with sufficient credibility and trust.