Artbitrage is very difficult with Bitcoin anymore due to transaction times. It is not like the old days. Sometimes, i have to wait an hour before receiving my coins. I think a system that alerts Ethereum and based on Ethereum could be better.
This is true as the btc price will keep rising the transaction fees will also rise and thus the opportunity will become negligible or will not exists in coming time. It will be more worth investing then doing arbitrage in coming time. Might be will need to find opportunity with the altcoins if it can exists.