Different numbers of players lead to different set ups. This can be pretty fundamental. If you’re playing on a site that only allows a certain number of people, then beyond balancing the number of crew/organisers you really don’t get a whole lot of choice.
On some sites, it’s a balance between reducing the cost per person and choosing a number of people that suits the game you want to run.
The more players you have, the more interactions they provide. In a smaller group, each player has a bigger impact. If you've got fewer players then outside events have more influence. The events we run typically have outside events for players to react to. We normally run one shot events where the characters don’t recur. The main driver for the players interaction are those outside events.
We’ve been involved in running banquets and weddings which are much more groups of players choosing to take a character from an ongoing campaign and interact with other characters from this system. Is this situation we provide food and the setting, and the players do the rest. In that case the situation determines who you invite ic.
Typically, half the people who tell you that they absolutely will be going to your event will actually pay. You need to be making enough money to run the event at about this level. Not having enough places for everyone isn't usually the end of the world. Pricing is also important. You need to cover the site cost and food at a minimum, and we typically need to include a van, set dressing, and props.
Mandala have a pile of resources from previous events that covers tentage, field kitchen, catering, set dressing, costumes and monsters, lighting, effects, computers, phones, electricity etc. If we’re using these typically we put them in the budget at a ‘maintenance’ cost - to ensure we can repair damage and improve on the kit we already have.
So, back to how many players. I like to have fewer, a lot of mandala like to have more. I tend to thing 20-30 is good. Everyone becomes essential. Your skill mix is such that there’s not too many of any particular role, and they’ll often work together. Our largest events tend to be about 55 people. In these we tend to put people into teams, and set them against each other a bit. It works fairly well, although with the dramatic hits system it does require everyone to play to the spirit of the game.
Our latest event was designed to have 35-40 players, and ran with 17. I personally think it ran better this way. It was a game for heroes and it gave everyone a chance to be a hero. Everyone was essential in a way they wouldn't have been otherwise. We had 9 different skill sets, and there were some that were unrepresented from the beginning, but people did get chances to change part way through.
With more people we’d need to split people up more, get the party to be in two places at once sometimes, because some of the encounters we run don’t work with the number of people present.
Running events where not everyone gets to see every set piece is also controversial. Players may feel they didn’t get what they paid for. If they miss something that people say was awesome, have we let them down? If everyone has to be part of everything doesn't that feel a bit like railroading? Small events that run as part of fest system worlds allow players to have experiences they couldn't have in uptime due to scale. As part of that we include experiences that are only for small numbers of players because they look good, feel good, carry the story well, and make awesome stories. It’s much easier to be scared if you’re alone. When watching a film, you know things have gone wrong when people start splitting up. It brings in new emotions.
This comes back to encounter balancing, and ‘Show, tell, do’. an encounter may be do for some players, show for others, and tell for the rest.
So, how many players? Enough that everyone is occupied and has enough to do. You can always split them up to maintain atmosphere. I mostly want fewer as it makes the admin side easier.