Very good, Charlotte. But be aware that post processing can take valuable time away from behind the camera. It is addictive.
If you are using photoshop, going along with what Rob said, always work in layers. Always name the layers as you go, and always save the image as a psd file. That way when you return to the image, you have a record of what you did, you can see the changes you made, and you can add or subtract or otherwise modify what you did with ease.
If you are using another program, perhaps someone else here has helpful hints.
I just saw your explanation of your work. That is a ton of work and planning, and you surely did a great job. It would have taken me days!!!
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