Assassinationhas a ton of extra critical chance which is great for both Single Target and AoE damage. The passive from slotting Soul Harvest (Death Stroke morph) offers an insane amount of Ultimate generation in fights with lots of adds. This line also offers VERY GOOD sustain for fights with lots of adds due to the Executioner passive. You also have access to the Hemorrhage passive which gives you and the group even more critical chance IF that is not already provided. This line does fall off a bit for fights where you can’t flank, as you lose 6.6% of your critical chance.

Aedric Spear seems to be capable of slightly higher Single Target damage. However, the Burning Light passive that contributes to a lot of the damage does not trigger in AoE. In addition to the bonus weapon and spell damage, Aedric Spear also gives a bonus to armor with the Balanced Warrior passive that you would not have access to with Assassination but is not quite as much as you’d generally get from Earthen Heart.

Dawn’s Wrath seems possibly the highest single target assuming you have access to great uptimes on crit damage buffs from your allies. This line does not have any crit damage like the other 3 options listed here though, so that could cause it to fall behind depending on your situation. The execute with Dawn’s Wrath is also by far the fastest of any of these options.

Earthen Heart is the tankiest of the choices as you provide your own Major Resolve with a very strong offensive skill and you have a strong Armor passive in this skill line. The damage is a little behind the other options but not that far due to some nice offensive passives including extra crit damage and a damage done bonus.

I think the Assassination line is most versatile and the option I’d go with most often, but all of the other options are really great too.