No not really. Like I wrote, this is a story about liquidity. The opportunities I found generally were in the lesser traded therefore lesser liquid coin-pairs. These pairs trade less often. It may not be the opportunities disappeared faster than you could make them, but rather, the data you had was old (.5 seconds or more) and that trade no longer existed. At least that's my take. When I set up the websocket and watched the trades update I was surprised how thinly traded some pairs are.

If I had more funding I would look at buying a direct feed from the exchange with a high data rate limit, thinking I'd get more timely trading data.