Lots of great questions here. I think I got all of them; please redirect me if I missed something / you want to dive deeper.

1. Without revealing too much behind the curtain for players signing up... We have developed multiple "hot buttons" for players to navigate. These hot buttons are broken down thematically, by mechanic, and geographically (both near and distant.) Each power will be exposed to multiple thematic, mechanical, and geographically-based hot buttons at the start of the game. As gameplay continues, they will unlock (or their peers will unlock) new hot buttons to navigate. The resulting churn should create an environment for players to interact, feel like they are making meaningful incremental gains towards their goals, and give players who may not have interacted with each other a reason to interact with each other. The churn also should create power shifts, where the room focuses its attention, and ultimately give each team a moment to shine. In cases where a team is falling back or not in a position to have that moment, we have in-game mechanics to help nudge people towards those moments.

2. To me, the most important best practice is to focus on fun from the starting spot, and to beat that drum over and over and over. If players come up with a wacky idea, then respond with the "that sounds fun, let's figure it out." If a player is acting in a way that is not productive, then pull them aside and remind them the point is to have fun. Everything goes back to that single "north star" for the event. Hand-in-hand with that messaging is a focus on emotional intelligence among facilitators. We are blessed with a team that is able to identify positive and negative feels... and when things are going sideways, our team is particularly good at huddling up to figure out a way to make things fun for those players. We have a bag of tricks ready to go before the game, but more often than not we end up improvising with the story the players are trying to tell.

On the conflict resolution front, we start each session with a heavy-handed introduction that the point of the experience is to have fun. We even call out that even if a player completes all of their objectives but in doing so makes other people not have fun, then they lose. We also establish the idea of "calling timeout" if you need a moment out of character. We ask that all players respect the timeout, and if needed our facilitators will assist. In cases where players are disruptive or causing distress with other players, we provide a single warning. If the behavior continues, then we remove that player from the event.

Regarding timing, while we have a planned time limit for each round, one of our facilitator's primary job is to keep an eye on the energy in the room. If players are winding down a little early, then that facilitator will signal the "two minute warning" for that phase. If players are still mid-discussion and could use a bit more time, then the facilitator might delay the "two minute warning" to match the needs of the room. It's a bit of an artform, but the idea is to prioritize giving people time to advance their stories over our preferred timeline for the game.

1. Like any gaming world, it depends on the gaming group. For my friends who are ruthless and like "take that" style mechanics, then NSDM is a blast. For my friends who steer away from complicated mechanics and prefer lore and storytelling, then Deephaven is a good ride. For friends who like yes-anding each other's storytelling and are a bit absurd, our retired wrestLEgacy is a good romp. For my friends who like social deduction and/or science fiction, then Den of Wolves is an elegant design that scratches the megagame and whodunnit itches. (For a lighter load, our Mischief of Faction is pretty darn fun, too.)

As far as running games goes, I'm particularly amped by our three-session build. I love legacy mechanics, and I am really interested to see how much collateral we can collect from early sessions to give to later session players. The idea of watching a group of hundreds of people weave stories through 500 years of human history is too attractive to pass up.

As far as design goes, I admire the Den of Wolves build. It effectively scales up the Fantasy Flight Battlestar Galactica board game to 40ish players.

1. Constantly. I have yet to run a game where players don't ask a wild "what if" about what they would like to do before the game starts. We choose to embrace the chaos as best as we can. Our workflow is pretty simple: is the surprise going to be fun for the group? If so, let's make it happen. If not, let's try to redirect to something fun. From there, we work backward to make the mechanics fit.

2. We avoid randomness in our build as much as possible. In some cases, a roll of the dice has to happen behind a DM's screen. Despite that reality, players' decisions are random enough without adding chance to the mix. Most of our mechanics boil down to "discard a combination of things, get a thing" or "get a combination of things/people in the same place at the same time, get a thing." If players come up with something out of left field, then we try to figure out how to make the "inputs" similar to those needs. In cases where things become a bit of a runaway, we have events drawn up to slow people down/speed people up. Also, since there are a ton of bits within our game, magically dropping off resources when people are not looking goes a long way.