Can individual tracking points be edited in After Effects?
(I can't comment because I don't have 50 reputation yet lol)

By the way, if I got what you mean you just have to move with the Selection Tool the keyframe on the Composition screen.

For making the path smoother and more accurate the sub-Pen Tool called Convert Vertex Tool.

Finally, on the timeline thanks to Graph Editor, add dynamicity to the animation in-between frames (delay and advance).