I think the brute force approach is pretty much a non-starter for the reasons listed above.
There is one brute force way that I think is still effective--probably the most effective.
But, it requires another ship.
I'm talking about a pirate attack.
You'll have to find an appropriate system for this to take place. Asteroid fields are great for this. But, some less populated systems will do as well. Even if the Players see the pirate coming, there's little they can do.
The players can either stand down and be borded, or the pirate vessel will open fire. Play a starship combat enounter. After some major damage to the PC's vessels, they are given a chance to stand down again.
When/if the PCs finally stand down, the pirate vessel will dock. Make sure you order the crew of the PCs ship to board the pirate vessel--don't send troops over there first. You'll (1) weaking their resistance if they kept somebody aboard to ambuse boarders, and (2) the pirates will have hostages to do dirty things to should characters still on the PC's ship resisst.
Then, people can be tortured, thrown out into space, whatever, until the correct codes to the vessel are provided ("Is this ship worth your life?")
And, if the PCs are lucky, they'll not be killed, but either marooned or left in a survival bubble (which means certain death unless another ship is near by).
A
great way to run this encounter is with another ship coming to the rescue. The rescue ship is on scanners, but its 1G drive can't get it there for several hours. So, it actually watches the whole thing. Sees the pirate attack, and is able to pick up the survivors after the pirates leave with both ships.
Another thing we forget to do in Traveller is remember how long it takes a ship to slow down. Take, for instance, a ship making a run, in-system, to a moon or other planet. Let's say it's destination is 6 hours away.
What will happen? The ship will accelerate at maximum G for 3 hours and then decelerate for the last 3 hour leg of the trip.
Well, wouldn't it be neat to set an encounter where the ship sees a pirate raid at about 2 hours into its deceleration? The ship is already decelerating at maximum G. There's nothing it can do but float by at high speed.
And, there will be a little window in there--maybe 10 minutes--maybe two space combat rounds--where the ship will witness the raid but be unable to do anything about it. It's moving too fast.
I did this once in my last Traveller campaign. The players needed help desperately. They got a call from a ship. They thought help was on the way. But, the ship was moving too fast! It would be hours and hours before the ship could change its vector enough to approach the PCs and help out.
What happened was the ship was in rage for combat for two combat rounds (30 minutes). I allowed it to particiapate for those two rounds. It's vector, though, was written in stone because it was decelerating on a long trip. So, the ship moved in a line, fired its weapons for two rounds, and was gone.
We even had a cool role playing moment as the player captain and the captain of the decelerating ship exchanged a few words.
"I've sent over a packet detailing who we are and who we think our attackers are. Please, send help at earliest."
"Will do. And, God be with you."
It was something else. The thought of coming across people in need but being unable to do anything about it.
Heck, that needs to be in a sci fi story somewhere.