While we're still on the subject of GGG plays, I want to touch on the game's subtheme of inter-party interactivity. Groups of PCs that interact a lot with each other are great fun. Why that is fun is something several hundred words could be written about, but let us for the time being summarize it saying that anything you do involving friends is fun, with the added benefit of making the GM's work easier by rousing folks to create their own content to keep themselves entertained.
Is there something wrong with playing individually? Certainly not, and any ensemble cast is going to have people whose goals and motivations take them in a direction the rest of the group will not see themselves involved in. That said, every GM has had to deal with a separated party at some point and let us just say that it is not an ideal situation.There are many ways to deal with this, but none of them are perfect, and thus the less it happens the better. Plus, parties that don't do much together beyond making robots blow up are missing a ton of chances to roleplay - the GM can never come up with content that is as rich as what the entire group can put out together.
Slice of life elements through episodic gameplay are encouraged so that the party is close, but not only that is simply not everyone's cup of tea, oftentimes it simply won't be enough on its own. Unless the players all sit down to make a party that works together well, they run the risk of a segregated group that wants to do their own thing leaving everyone else outside of it.
Roleplaying Games should encourage the type of game they want people to play through mechanics, and GGG at the very least provides incentives for party interactivity (though not necessarily unity) through its rules. A Dramatic Typecast will make people more powerful for roleplaying with the rest of the group, either for their mutual benefit or by causing conflict. Some of the most powerful Genre Powers are those that benefit other PCs or that benefit the entire group - Helping people bond simply by the fact that PC A saved PC B's life thanks to Not so Fast. The Teamwork subset of Upgrades are some of the strongest in the game, providing ludicrous benefits at a price. And so on.
I'm trying to get the point across in these posts relatively fast while the game is still fresh and as time goes on, I will be glazing less over the details. For the time being, I hope these simple overviews suffice for anyone who has doubts over how to run or play.