Most defensive or even trasportation powers could be used as an offensive
Indeed. Like, my top choice for for both offensive and defensive power would also be mind control; offensive in the sense that I can make people do shit, and defensive in the sense that I can stop them. Meanwhile, what about powers that aren't exactly either offense or defense? I would actually wish for telepathy, which means reading minds in addition to controlling them. Reading minds could be used in devastatingly subtle ways, and I would be all about total discretion.
For a transportation power I guess I would choose teleportation, but really I find this category kinda lame since there are really only about three superpowers that'd fall under the category of "transportation": teleportation, flying, or running super fast. I think the real challenge would be thinking of a way to twist your transportation superpower so that it fits your character's theme. Like how jimmy put a shadowy twist on teleportation to fit his theme. In my case, because of my whole mind control thing, I could explain the teleportation as a side-effect of the subjective nature of reality, where if I make everyone think that I'm a hundred miles away, then I actually
am a hundred miles away.
Come to think of it, that could be a really cool limitation on my teleportation: I can only teleport to a spot where someone else is already present, because my teleportation is dependent on messing with their head.
EDIT: Actually y'know what, if I could affect consensus reality like that, what's to stop me just changing reality in any way imaginable whenever I felt like it? Too powerful, I just wouldn't have any transportation ability, unless you count mind controlling people into opening locked doors for me.