ok, if you think about it logically a bit,

goku > teleport from this place to that place in a .... flash , distance = extremely far
ichigo > same thing, but shorter range.

and despite the range, as much as i know, to do the instant transmission, goku must touch this forehead? > slow start time.
(and no, the teleport kamekameha was just a fast moving one, = ichigo speed, not that much more)

about the damage part, read some comment, i can't be bothered typigng all again