[AKA] Fun with Cinematics

I finally hosted the first real one-shot playtest of All Kinds of Awesome, which began as a Tri-Stat setting but for which I've now made a significantly different system.

The four major aspects of the system that I wanted to test were:
a simple task resolution system using five unmodified attributes,
a single hit point gauge called Dignity that was used for both physical and social combat,
NPCs called chumps against whom the PCs can succeed at literally anything,
and the use of player-narrated "cutscenes" during combat that feature nondiegetic cinematic and video-game effects.

After a brief description of the campign world, my players created their characters, a robot from Steam City and a priest of the Flying Spaghetti Monster. I told them about the city they were in and explained that the PCs were motivated by the desire to prove the superiority of their paths to power by ending the city's gang war between the Beard Wizards and Moustache Magi. One player was surprised that I had backed up my assertion that it would be important whether his character had a moustache or a full beard.
After a little goading on my part, the PCs began quarreling with one another. They figured out that interplayer rivalry was encouraged, but I think that I could have done it more quickly and effectively. I think the way in which my system gave PCs a limited selection of "attacks" interfered with their ability to narrate their conflicts.

Things went along fairly smoothly from there, as the PCs investigated facial-hair-gang activity. A short combat encounter served to teach the players what chumps were. I was surprised by the rate at which the pC's dignity was worn down by their various social encounters, but I believe that the dignity system really helped them get into the mindset of a character obsessed with power and image

The game, to my amusement, became almost completely freeform, and the only page that my players ended up using was the list of suggested cutscene effects. During the big final battle, the priest's player beseeched the Flying Spagetti Monster for direct aid, which turned into a hilarious social encounter. Both players obviously derived a great deal of enjoyment from narrating cutscenes and chump deaths. Things even got somewhat cerebral as the players determined how to use the abundance of chumps in the final encounter to their advantage against their non-chump adversaries.

Though the session was successful as an event, is a degradation to free-form play useful to a playtest? What are some useful ways for quickly conveying a game's premise/specific social contract? Is there anything important that I omitted from this post? Apart from answering these questions, feel free to respond in any way whatsoever.