This mod provides a menu at the beginning of the game, after the bathroom scene, with three options:

Alternate start: wake up from this dream as a different person, not the parent of Shaun:

You can be a pre-war vault dweller, starting in Vault 111:

Follows the alternate plotline, where you are released from the vault by mistake

At the terminal, select your own SPECIAL stats and up to 20 traits

You can start as a wastelander outside of the vault, and select:

Your own SPECIAL stats

Up to 20 Traits

One of 38 different occupations, including factions (affects your starting gear)

One of 38 different start locations (sorted by difficulty)

How much or little starting gear you have (four difficulty levels)

Your starting level (so you can pre-level-up your character)

Randomize any or all of the above

This mod is minimally invasive, and makes only as minor edits as I could get away with.