Ide say start with a longer timer and taper it down to a minute. That way people have time to examine the resources and gauge their value.

But to lose the timer seems like a loss of the strategic option of intentionally breaking down negotiations.

When playing Cosmic Encounter I’ve sometimes felt the minute turn timer is just a touch too short. By the time you take stock of everything the other player has and start to actually discuss it you’re almost out of time.

Could you replace it with a 90 second or 2 minute timer? Simple negotiations will still go quickly but that way more complex ones will have a bit more time to breathe.

90 seconds feels right to me.

One game I played a few years ago had a really neat rule that I've used in a lot of other games and contexts.

The game came with a 1 minute sand timer that didn't have to be used to play the game. But the rules said "If any player feels like the turn is taking too long, they can turn over this timer. This is a signal to the current player that they should wrap things up". I can't recall which game it was. Codename, I think? I'm sure someone here will let us know.

I've used that rule in a lot of different places. If you have a healthy relationship with your co-workers, it makes for a really useful tool for keeping meetings rolling. We occasionally mime turning over the same timer to each other to say "I respect what you're saying, please continue, but also let's get this back on track".

I've also ported it to many boardgames. In my circle of players, turning over an imaginary sand timer is a way of politely saying "we like playing with you, but we're feeling bored so please make a turn".

Maybe something like that can work for your group? It requires some communication up front to ensure that people know the spirit of what's being communicated.

Edit: re-reading this, I'm not sure I conveyed what I was suggesting well. Cosmic Encounters has a 1 minute timer you're supposed to use. I'm suggesting making that timer optional. Let people barter until someone at the table feels like enough time has passed, then flip the timer as a polite way of saying "please wrap it up".

You have to take stock of your goals for the evening. E.g., does the game need to wrap up at a certain time?

I'm someone who doesn't mind playing a game for literal days. However, if you need the game to end at a certain time, then that means there's an implicit time-limit on play. That, to me, strongly suggests you want to keep the timer in play.

I would make the decision up front that the timer will be in play and decide for yourself what a maximum timer duration could be for your time requirements. Then, I'd announce it to the group ahead of time and allow the group to discuss what a reasonable timer duration should be.

As an aside, time limits like these are often not arbitrary and are part of the rules for game or experience reasons. Bullet is supposed to invoke similar feelings to a bullet-hell shooter. Removing the time limit, to me, seems like just choosing to play an entirely different game. A significant part of the game is being able to make decisions while under the stress of a time limit.

Similarly, I view the timer in Cosmic as intentional. The original Eon edition called the cards "Compromise" cards. I believe the intention was to force a compromise (as in, neither player necessarily gets an optimal outcome) I think it hurts the game to allow players to be able to entirely analyze the situation in order to make an objectively optimal decision.

My suggestion:

Tell them there is a timer but also explain that it might not be enough time so some leeway will be provided. When timer is up, tell them they have to wrap up in 30 seconds or lose ships.

Reason: People hurry up when they are reminded that they passed the deadline already

You could try softening the fail state. You could either extend the timer, maybe with some kind of warning time to hurry up. Or you could have them roll dice to extend the timer.

Maybe the easiest way though is to detach the limitation from time entirely. Instead of keeping it to a minute, you could try limiting the number of trade proposals each player can make. So say each player can make 3 offers, going back and forth. If they don't land on something after each of them have done their haggling, then the deal breaks down.

It could add a new level of strategy to trade, as it adds a cost to each attempt at haggling. It turns up the stakes, but it puts the control in the players' hands and encourages efficient communication without just wagging a timer at your players.

I'd probably do that.