No, higher bonuses are already an option. Check Listening (YS 153). +4 to Investigation rolls for hearing, but alertness drops to Terrible while doing so. It doesn't require the expenditure of a FP either.
Now, Listening comes with a built in drawback for using it, and has a relatively niche application. Whether or not the Intimidation stunt above is sufficiently specific and limited enough to qualify for a +3 bonus without expending FP is up for debate.
Now, if the stunt under discussion is only applicable to the Threats trapping of Intimidate I would say it is definitely limited enough to qualify for a higher bonus, since it requires a fairly specific and non-inconsequential opening condition to come into play.
On the other hand, if it can apply to any trapping of Intimidate once the activation criteria are met, I'd say that a +2 bonus would be more reasonable. Admittedly, if you brutally murder someone Social Combat is probably off the table, but I can definitely see the application to Interrogation and Provocation, and maybe the Brush-Off.