There are a few situations that keep on coming up in my tremulus game that I don't really know how to handle with any of the default moves. That is to say, players keep having their characters do things that I would expect (or would prefer) to trigger them to roll dice, but none of the moves available seem to fit. Dungeon World offers the various Defy Danger rolls as a catch-all method of handling "I try to do this thing, it's difficult and potentially dangerous but it doesn't fit any of the other moves". But the closest analogue in tremulus is Act Under Pressure.
Act Under Pressure works reasonably well as a sort of cut-rate Defy Danger for the occasional hard-to-represent situation. The trouble is that there are a few hard-to-represent situations that are anything but occasional.
Consider a situation may seem rare but which comes up in my game at least as often as Convince or Threaten do: A character fires a gun (possibly from stealth) at a distant or physically impeded enemy who can't fight back.
This isn't (at least, I feel it probably shouldn't be) Resort to Violence. Resort to Violence comes with the implicit fact of retaliation, and here the character has gone to some effort to ensure they're only attacking in a situation where retaliation is not plausible within the fiction. And if this roll is RtV, then the character who expends rolls and resources and makes choices with the intent of getting themselves in a safe firing position has gained entirely no advantage over the character who charges in guns blazing.
This could be Act Under Pressure. But should it be? I'm a little unhappy with the way this a) seems to make Reason the single most important stat, b) suggests that, in the fiction, the character is using their Reason to overcome the problem even when this makes very little fictional sense, and c) binds the outcome of every such question to the worse outcome/hard bargain/ugly choice 7-9 result.
The GM, concluding that this situation doesn't trigger a move for any of the players, could simply make a move in response (effectively, narrating the outcome of the player's action). This feels awfully capricious - sometimes that's okay, but sometimes I'd prefer to let the players to roll dice or at least have some sort of framework to handle this situation rather than just making a snap decision as to whether they succeed, screw up, or what.
The GM could make a custom move for this specific situation? This seems like it may be the way to go, but what would such a move even look like?
Other situations that come up often (perhaps suspiciously often) that I also don't know how to represent mechanically in a nice way:
A character tries to sneak past (or sneak something past) some sort of guard or sentry. (This one fits fairly well as Act Under Pressure and I have less of a problem with it.)
A character tries to physically resist or endure something that can't be fought (e.g: a blizzard, sleep deprivation).
A character wheedles, begs, or pleads someone for something, offering nothing in return.
How should I handle this sort of situation in line with the PbtA philosophy? Am I overthinking this? Is there something obvious I have missed?
Note: Not a duplicate of What do you do in Dungeon World when someone wants to perform an action they don't have a move for? - this question is the result of me attempting to apply the answer to that question to the narrower and more focused system of Tremulus and not being entirely satisfied with the result.