There was zero wind so a drift anchor wouldn't have done anything for me that night. The way points are on the boat gps so I'm not sure how far I drifted exactly but I think it was less than 5nm in 6 hour period. Drift speed is a function of wind, current, and boat type so expect lots of variation. I've personally never used a drift anchor but I've heard guys have mixed results. If there is wind and you can figure out how to set the drift anchor so that it actually holds your boat with the nose into the waves it would be beneficial.
I had my radar alarm, AIS, and set my alarm to make sure I didn't sleep for too long. It was basically an all nighter. Maritime law states that you can't go more than 20 minutes without having someone on watch (...something like that). If you have a good crew of guys it is best to switch off watch every couple hours so everyone gets some good rest.
Of course I'm worried about shipping traffic. And cruise ships. And other fishers, commercial or recreational. And yachts. And breaching whales. And fatigue. And incorrect weather forecasts. I also encountered the same log (very distinct) on two different days about 20 nm apart. As large as the ocean is there is also ALWAYS a chance of collision with something. You can only ever minimize the risk, never eliminate it. I'll do it again in a heartbeat.