GuardianLurker said:
Writing adventures for teams of players. Once I move away from my D&D roots, it gets harder and harder for me to find inspiration for team adventures. I also have trouble balancing the few adventures I do find.
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There are exceptions (anime, military fiction [though not espionage fiction], superheroes), and not surprisingly, it's pretty easy for me to set adventures in those genres.
I have to emphatically agree with the superhero genre, here.
Based on the comments in this thread about the "user-friendliness" of fantasy, I have to say that, IMHO, supers fits the criteria for both being easy to run and allowing anything you can imagine to much greater degree than fantasy. Given that supers is a meta-genre in a way, I think that fantasy is way more of a straightjacket.
First off, you don't need hordes of NPCs in a supers game, unlike D&D-style fantasy. You need a team of heroes (the PCs) and one or more villains. The heroes can be brought together by reasons as flimsy as "you've joined forces to combat crime," and said reasons don't break SOD nearly as much as the fantasy cliche of meeting up in yet another tavern and being approached by a wizard. The opposition can be someting as minimal as a single powerful foe with various henchmen, or simply an equal number of villains at roughly the same power level of the PCs. And since it's typical for the villains to be captured (as opposed to slaughtered), you can re-use them all the time.
Secondly, unless you really feel like going in-depth about the supers-related background of your world, there's really no world-building necessary. It's the real world, plus supers.
I Gm'ed a lot of supers games back in the day--mostly V&V. You could have PCs ready and wing a night's entertainment with very minimal prep, something I generally find very difficult to do with fantasy.
Anyway, my point is simply that I agree with many people here that "ease of use" is simply not the reason. IMHO, genres like supers and horror are both more accessible to the average person and far easier to prep. I'm much more inclined to agree with market forces and literary influence, m'self.