After ten or so sessions of GMing Freebooting Venus, I sort of feel qualified to comment on various parts of the game and how well they're working for me and my group. It feels like a natural thing to do - I hope it's going to be useful feedback. I'm going to start with the moves, one by one.
Demand Something
This is one of the moves they most often make (second only to Recover, Regroup & Prepare, but barely). That's probably because it feels like a "versatile" move we can stretch to cover quite a wide range of fictional situation - for example, Enrico's PC Vetin often tries to get her way out of trouble by telling outrageous lies and, more often then not, we resolve that as Vetin effectively demanding that people believe her bullshit. Demands to be left alone are also matter of course.
As a GM, it feels different from any other move, in that it always requires me to inject new content into the current situation - effectively making a move of my own on the PCs - even on a hit. Which is actually great, most of the time: by choosing to roll this move, they only make their situation more complicated. To me, that's always an opportunity to evolve trouble - sometimes escalating it, sometimes creating new connections between previously unrelated situations, and sometimes handing the PCs new "jobs" altogether. These things sometimes spring from my prep, but most of the time it's just content I improvise on the spot (and add to my game prep notebook later): sometimes this marks the beginning of a whole new adventure. That makes it a slightly taxing, but very fruitful move, when observed from the GM side.
Sometimes, though, it felt like a pity there wasn't a superior success option available (on a 12+ or whatever) to have the demand met with absolutely no strings attached - because, once in a while, why not?
The problem with this move is when a PC initiates it in a way that obviously signals their means to their end: when the demand, before rolling, is accompanied by a threat of violence, an extravagant bribe, or phrased as a bluff. The problem being that, as the GM, I find myself effectively having an extra layer of choice to make on top of what the move always asks of me, i.e., whether to give the PC a "free pass" or not. Let's say a PC lies to an NPC and threatens them with violence just before formulating a demand and rolling, and hits in the 7-9 range: I can take the cue and say "They'll do it if you deceive them and threaten them", effectively making it an unmitigated success from the other player's standpoint, or I can choose either 1 or 2 different options, thus complicating the current situation.
OTOH, when I choose "if you deceive them" and the player making the move isn't already performing some kind of bluff, it feels like I'm judging their performance, evaluating whether and when it's enough (and good enough) of a deception.