@ThisIsACoolName, what kind of Improv troupe are you? Are you at all similar to Tim and Eric (sorry if you hate them)?
I don't watch Tim and Eric, but a quick google search seems to indicate that they do a sketch comedy show.
Everything I do is 100% improvised. I do not plan ahead and I never use scripts. As stated previously, I perform as a member of two troupes: Angry People Building Things and Capital t. Both perform what we call "Long form Improv", where we do an entire show based off one suggestion, gotten right at the beginning (usually a single word). Long form generally consists of straight scenes (as in there is no gimmick) with no breaks in between- when one scene is over we immediately start the next one. A standard long form set is about 30 to 45 minutes. Again, this is 100% improvised.
I also direct/ coach a troupe called Women With Class, who are, as the name would indicate, all women. They mostly perform a style of improv called "Short Form", where they do separate games. If you've ever seen
Whose Line is it Anyway?, that is essentially what they do, except the games (or "structures" as we prefer to call them) are much more focused on the scene and less on the gimmick. For example, one of their most frequent structures is one called "Actor Narrates Actor", where two of them perform a scene and periodically step out an narrate for the other performer. Another one they do a lot is called "Rashomon", which is where three of them will recall a disaster or catastrophic event, each from their own characters unique point of view, and their recollections will reference/ connect/ differ from each others. The classy ladies are also capable of doing long form, but they usually don't.
Short form is generally more accessible to an audience unfamiliar with improv (it has breaks, a lot of audience participation, short scenes, etc.) and, somewhat ironically, lends itself to longer shows. Short form sets I've worked on have ranged in length from 15 minutes to two and a half hours.
