Well, Caluurion has been nerfed, so not that.
I've been hit pretty hard with the non-DOT portion of Deadlands Assassin, e.g. for 6K against a squishy build. As far as I can see it does not have the obligatory 1s delay that many sets have. It's also stat-dense for a proc set, e.g. 458 wd / sd plus a line of stamina. Maybe combine with Vateshran 2H back bar, since that also procs from a heavy attack.
Snipers seem to go for Scavenging Demise, but that has a long telegraph and can be dodged.
Rush of Agony is more of a bomber / AOE group play set, but I've been solo ganked with it also. Ambush into an ultimate (Incap, Tether, anything that stuns) lets you combine the ulti with the proc and an execute within 0.6 GCDs. If your ulti lands and stuns, the target can't react. It also does that annoying pull, which should help keeping the target close after Ambush.
Ganking squishy players has become boring, it’s more satisfying when ganking a dk instead. I’ve seen a video of this player ripping through DKs and templars with sea serpent coil at 35k+ health. They were using onslaught for 100% penetration followed up with blood for blood at really low health.
Is it better to go with proc sets or max stat sets?