Roleplay-wise, a Durge that intends to embrace the power at any cost aspect would very much make sense as a warlock (because obviously), a sorcerer who's really into how very very special they are, or a wizard, because isn't it a rule that wizard are power-hungry and self-absorbed?
You are damn right. But my fear is that the "Urges" actions will be represented as raw violence (like what happened to Gale's hand) so i want a char that could produce that raw physical violence (avoiding caster and/or halfling/gnome). So i will wait to see if Melee Warlock are a thing.
One of my other idea is a Human Rogue assasin to play Durge, to represent my most hated evil character i met in books "Lijah Cuu". I guessed that a pathological murdered and psycho would fit really good for Durge, but at the moment i still have preference for Oathbreaker.
You can play as a dex based Warlock that uses malee, although it will be scuffed. Your main option.. knowing hex blade is not in game- although a hexblade Warlock mod already exists, first result on Google search.
1) (swords) take Rogue to level 3, take trickster , at level 4 use your feat for Warlock initate (hex spell, and eldrtich blast). At level 8 Rogue take Mage slayer, at level 12 Medium armor master or Warcaster
2) (ranged) take eldritch knight (3) and 1 Rogue. Dump strength for dex and charisma. Take Warlock at lvl 4 as a feat. Take eldritch knight until lvl 8. Take warcaster, Take spellsniper as a feet at lvl 12.