I had a lot of fun coming up with a thematic Dark Justicier for Shadowheart. I went with a Oath of Vengeance Paladin paired with a Pact of the Blade Warlock. This was an amazingly fun character to play as my primary companion. I also felt it fit her better to be a Charisma build with the main plotline of having lost her memory. It always seemed a bit off for someone with no memory to have such a high wisdom TBH. As a bonus, I did this on a Dark Urge playthrough and
killed the Nightsong
. Eventually I had to accept her as an Oath Breaker Paladin because lame things kept breaking her oath
(seriously, why should fighting guards in Moonrise Towers break her oath?)
. At normal difficulty, she had 3 attacks per turn at level 10 with all of the Paladin smite goodness. When out of melee range, Eldritch Blast is a great option!

"He that can smile at death, as we know him. Who can flourish in the midst of diseases that kill off whole peoples. Oh! If such a one was to come from God, and not the Devil, what a force for good might he not be in this old world of ours."
-Bram Stoker, Dracula