Since this was started to break the discussion off from the background instead of feat discussion, I'll repost my response here:
I love level-0 games. I use the Dungeon Crawl Classics zero-level funnel and apply to 5e. Basically, each player gets four zero-level characters. The idea is that most of the characters are going to die. Typically, the first adventure will either be a group of brave non-adventurers brought together by some event that would lead a fairly large group to come together to address, e.g.:
- A posse is put together to hunt down some baddies, free someone captured from the village, exact justice on someone who wronged the people of the village, etc.
- A sink hole appeared below Abe's house, and Abe and his house fell into some ancient ruins that nobody knew were located under his farm. A brave group goes to investigate and hopefully save Abe.
- A group of people of all walks of life is enjoying a traveling circus, which is actually a group of cultist who plans to perform dark rituals and human sacrifices.
You get the idea. In a four-player game, there will be 12 characters, in a 6 player game there will be 24, so it needs to be a scenario where that will work. It won't be a stealth job. The idea is that most of them are going to die. Of those that survive, you select one and choose a class.
It works well because it gives an origin story to the party that the players play an active role in making. It works best as part of a session zero so that nobody is disappointed if they were expected to come in with a 1st level character with a rich backstory written up and expecting to have plot armor protecting their precious, single character.
I'm going to be using this for my next campaign and here is how I am thinking of doing it:
I will schedule an 8-hour chunk of time for session-0 discussion, character creation, a level-0 game, lunch, and general hanging out together.
Session 0 will be maybe an hour or two. Everyone will be given a sheet of paper that is split into four sections. Each section will have a form for basic stats and equipment. All players will create four characters. Stats will be based on standard array, because it is quick and helps prevent players from getting too attached to their characters at this time. Next everyone selects one background for each of their four characters and adjusts stats, proficiencies, skills, and equipment accordingly. That's it. Noboby is allowed to write up any background for their characters at this time. That is done as part of the level-0 game.
Next, I run a four-hour introductory adventure to the campaign setting. My next campaign will the be the 5e conversion of Rappan Atthuk, which was recently Kickstarted by Frog God Games. For this adventure, I plan to have the party as members of a merchant's caravan travelling along the Sea Coast Road on their way to Felkor's Ferry. There will be a some small events to set the scene and one major encounter/event that will be the party-defining event to kick things off. It is up to the players to decide why each of their four characters is travelling to Felkor's Ferry and how the events shape the motivations of the surviving character they choose to continue with.
After the adventure, each player selects a surviving character and selects a class for it. This will be a group exercise.