The sprouts remind me of the Koroks from the Zelda games. Or maybe the Junimos from Stardew Valley? They're all kinds of fun little forest sprites
I want to see them playing more. Could you have a few playing hide-and-seek in the scarf? Making mischief with the human character's shoelaces? Dancing with a flower? Swinging from a thread hanging over the tree branch? Throwing around acorns, or fencing with tiny twigs? Maybe another one stuffing its little face with something tasty? So much you could do with them.
As for background ideas, my imagination is going for a collosal mama sprout forming a big hill in the background. I've been drawing lots of hills and valleys and mountains lately - they're fun to layer up.