Now Warlocks are crazy fun to play!
Tiefling is a good choice here, but the very versatile Half-Elf shines brighter yet again.
StatsNow at level 4 you can take the Elven accuracy feat to bump you to 18 charisma and have even better accuracy when you get advantage on attacks.
Advantage is easy to get with a Warlock if you use the Darkness/Devil's sight combo or Hunger of Hadar later on (provided they put the latter in).
I like this background with Titania as a patron (Cuz she is Chaotic Good). Evil characters feel icky to me (personal preference).
ArchfeyThis background is really nice for a ranged blaster, as you can use a reaction to teleport 60' and turn invisible should you get hit.
Spells are sparse, but you get them back after a short rest. I usually pick out of combat utility spells along with a selection of in combat spells to pick from such as:
Darkness, Hex, Mirror image, and Armor of Agathys.
Eldritch invocations are abilities that can be chosen as you progress and are quite powerful. Agonizing blast is pretty staple.
Eldritch InvocationsWarlock SpellsClass OverviewEldritch Blast is a cantrip that you can cast without a spell slot. It has a 120' range and uses force damage (rarely resisted). cast 2 blasts when you reach character level 5.