In TMP, Spock travels through V'Ger and sees a representation of V'Ger's journey including the Epsilon 9 station (and the Klingon ships in some versions IIRC) as well as various planets, moons etc.
Do you think V'Ger had assimilated the planets as it had the Klingons and Epsilon 9?
There were never Klingons seen in the Spock Walk. It was in concept art and perhaps storyboards, but never in the film. Spock's spacewalk, from the moment he fires the thrusters til when Kirk catches him is exactly the same in every edit of the film.
It's an interesting question about exactly what those "dimensional images" were. There are images of galaxies and so forth, and it's beyond unlikely that V'ger "patterned" 400 billion stars. I'd say that the images represented everything V'ger saw, scanned or digitized (unless it zapped the planet that made it).
The next question is where were these images when the Enterprise was drawn through the same orifice? Did V'ger switch off its memories? Or was Spock not "seeing" as much as getting the mental impressions since he was flying through whatever constituted V'ger's memory?