Is it a good card, yes.
But game-changing? Hardly. I mean if i have a good shot at the shuttle With say… Wedge, hell i will take it and the token. Certs it makes rebels a little more predictable but it comes at a 3 point cost and it is very situational. In many cases and situations the token will not affect the game in any way. If a K-Turn is not needed subsequently, i think it will have no effect at all honestly!
Leaving aside the logic of "it's a good card" and "it will have no effect" in the same argument, I think you underestimate the impact here, for a few reasons.
First, the stress won't clear just by not K-turning - you have to do a green. For an X-wing that's not packign an R2, that give you a 1- or 2-ahead, and a 1-bank to choose from. That's a pretty limited set of maneuvers, and you're faced with that or losing your action.
Second, because it's the first ship that fires at the target each turn, it's going to disproportionately affect high-skill pilots. A classic Han Shoots First list will see Han eating the stress most of the time. Wedge, Vader, and Fel will also catch it a lot. It's really going to screw with Fel, whose playstyle expects to be picking up (and clearing) a stress each turn to keep his focus factory running. Give him two, so he's got no actions next turn, and he's a 30-point Academy Pilot.
Third, it piles stress on. K-turn and fire? Two stress. Kath running this can easily build a ship up to 4-5 turns worth of stress.
Finally, it may be showing up with the shuttle, but this is going to be an outstanding card on a Firespray. Making your heaviest hitter dish out stress when you attack him? Oh, yes please.
I was not contradicting myself, i just said it is a good card, but not game changing.
You are being extremely optimistic there.
A-wings and interceptors, especially Fel and Tycho can basically go green manoeuvers all day, plus they don't really care about stress tokens. Yes, Fel gets only one action, so does Tycho, but the ebb and flow of battle also don't leave them with a firing arc on that ship with the Fugitive every turn. So they will be able to get rid of stress nearly every turn and will not really stop shooting or taking actions. Also this is only assuming they play PTL, in any other case you are basically giving Fel a free focus only, and Tycho, well he will still just not care…
Concerning Han, i have played him a lot, and he does not really care a lot about stress tokens. Give him a gunner and he is fine even without actions. That is why i constantly win against swarms with him that try to block him down. I mean even if they succeed, i usually damage or kill a different Tie every turn. A shuttle or firespray will be no exception especially with agility one/two. You can say i am optimistic now, but that's my experience.
It will bother Wedge (and Vader), but Wedge will not stop shooting you for this. And really the only reason to not shoot would be a K-Turn absolutely necessary on the next turn. And as you said, with an R2, he will barely care at all. Very often, even with only an X-Wings natural green manoeuvers you will keep the target in sights, because a Shuttle will be probably not very manoeunvrable, and a firespray is surprisingly limited especially in an asteroid field.
Kath… that's a good one. I literally have never seen her skill be effective in a game at all. Not when played her nor when i watched her play. The captive may at least assure that you can reliably dish out some stress tokens like you are supposed to. So i suppose you would take marksmanship and the captive for her, and then optimally you would give 2 stress per turn to an enemy. That might do the job for you actually, but then a crit needs to be cancelled, which happens surprisingly seldom really. I really see her as the only one really running the Captive, because everyone else will only dish out one token per turn, potentially cancelling a K-Turn or forcing a green manoeuver but not much more. But at 2 or more tokens, it starts to get interesting like you said.
As is said, it is playable, will be sometimes very useful but far from always. So a good card but for 3 points nothing compared to something like a stealth device or push the limit. So not gamechanging, i think.