Play a Dragonfire Adept? Seriously, it's the fixed Warlock. Just change the fluff, and you're done.
A Grognard's Guide to D&D Next/5E Rules Spoiler: Other stuff I've done Show 5E Rogue's GuideExtended Homebrew SignatureNiche Ranking SystemGuide to Melee CombosIncreasing Size, Unarmed Damage, and ReachHow to get Pounce or Free MovementX stat to Y bonus