Background Shot with Animated Characters

Here is my finished 2D background shot with parallax and animated characters:

I would like to improve my animated characters and put them into this shot again, especially fixing that some of the characters only appear part way through the shot and then disappear as well, which I was trying to fix before handing in but unfortunately didn't have time to properly figure out, even after extending the beginning and ending frames and putting them into the after effects composition again. I'd also love to properly clean up and colour the characters on the left, also making the picnic characters interact more and also offer food to their son who's skipped along to them. In the end, the background shot also seems to be from above, so I need to redo the child so that he isn't from a straight side profile, but from slightly above instead.
Overall, I'm really happy with how I coloured and rendered my background shot, however it would be nice to spend more time making it more in the style of Marc Bohne, especially the tree and the grass. I'd also add in a shadow of a cloud to the stage area, so it matches more with the background and the sky.
I would also make it so the child skipping would be in shadow when he runs under the tree and then comes out into the sun, as this would really make him fit more in the scene. I would also add shadows using the colours from the background under the character animation so they are more realistic and fit better.
I would also really like to change the foreground so it fits more with the landscape, as I feel like there aren't enough trees in the mid ground and background for it to make sense to have them there and placed in the way they are. Possibly adding more trees to the whole background and also drawing trees in the foreground at the top and bottom of the frame a bit more could help, possibly even adding in an animation of a leaf or two falling from the top of the foreground.