I was thinking about why normal plane changes are more effective when done far away from the planet and it seems to me that a planets spin would make it so that the plane change was more affected by the rotation of the planet if done from further away.
When looking at this effect on the map, it wouldn't be a laterally flat oblong around the planet that the craft would take when it did the plane change, but would be a lateral logarithm that pulls the craft along the direction of the planets spin most when at periapsis.
