Seems like Vader is the obvious candidate for Expose (as well as Daredevil), he's the only one that can sacrifice an action since he has two. Never seen an Exposed Vader so far, wonder why? Exposed and FCS would have him look more dangerous, especially since he will have some other action (evade, focus?)
I've used expose on Vader before, mentioned in this thread already. Its a solid addition, but it ends up making Vader a serious point investment at 37 points (always run vader with at least a concussion missile)...