Warpiglet
Adventurer
Sometimes it's not purely optimizing, but taking a weird concept and making it as optimized as you possibly can in the rule set.
I play in a game that meets once a month, the DM just rebooted the campaign at first level. All the characters are supposed to be descended from one of the gods in the FR pantheon (giving us an extra feat at first level, but nothing else).
My character is a descendant of both Tymora (goddess of good fortune) and Beshaba (goddess of misfortune) - He's a halfling noble (was lucky enough to be born into the right family), his bonus feat is "Lucky" and he's a Sorceror (Wild mage) and soon will have 2 levels of Wizard (Divination). Basically he controls fate - re-rolls 1's automatically (halfling luck), can roll an extra D20 when he needs to (luck feat), can grant himself advantage when he needs to (Tides of Chaos), and can alter fate for himself or others at higher levels (Bend Fate from lvl 6 wild mage and Portent from lvl 2 wizard diviner).
He gets his spells two levels later due to the two levels of wizard, but it gives him Portent and Ritual Casting for several 1st level wizard spells. Not super powerful, but he definitely has an impact on events.
Those extra thematic integrated characters are the ones I really enjoy reading about and playing. I have been babbling about a fallen acolyte I am playing who is a warlock, seduced by the dark side. I am taking magic initiate with cleric spells. It all fits together so far and makes it more fun to play.
Far from optimized, the theme is fun. Nothing like playing a puritan with a low wisdom who does not realize he is actually following a fallen angel...while he tries to make the world clean and right and pure.