I've only deep dropped a few times but have been successful most of the time. I generally fish in 650-750ft with 4-5 hook rigs with different sized hooks depending on what that area produces but generally a 13-14/0 Mustad 39960 circle hook works great all around. I add a light at the top of the rig and have found that without the light your bites decrease by half.Bait up with strips of cuda, AJ, blackfin, bonito or squid. Weight size will be determined by current but if you just go ahead and throw 5lbs on it, you shouldn't have a problem holding bottom. As far as bottom relief and what will actually show on your depthfinder, zoom in with bottom lock feature to within about 50ft of the bottom and look for any ledges or rockpiles that provide any kind of cover. It may only be 2ft of relief but that usually all it takes.
There are other members that know far more about it than I but this is what has worked in the past for me. I plan on further refining my techniques this year