Hm, I'm not quiiite sure what's going on here? (Ok, I get what's going on from the title.) I think what stands out to me, in terms of problems with the piece, is that so much of this piece is just pure green, which means all the figures are just floating in negative space. I think if you had shaded the piece a little differently so that the slope of the hill was more obvious, or had the... path? leading from the hut? be shaded as well to suggest a texture and perspective, that there'd be a stronger sense of place.

I'd also note that you have a lot of shades of green being used in this piece, but all of them are being used on the seated figure's clothing and none on the terrain. I suspect this was done to make him stand out, but this is the wrong way of doing it. (This is sort of like how people overemphasize the "interesting" features of a face when they do a portrait, and the forehead, neck, etc are neglected.)

If you're trying to emphasize a figure in a space, you want the environment to be more vividly detailed/shaded and the figure to be simpler. This approach would be especially helpful on the kids playing soccer, who right now have very finicky shading that makes it hard to read what they're supposed to be. Hell, even if you don't want to get super detailed, even a bit of a shadow would make it look like they're in the space instead of floating in negative space.

Composition here also looks a little off balance in terms of where stuff is placed, but I'm laying it on too think right now anyway. My main point here is when doing a big piece like this in the future, don't just focus on the main point of visual interest - make sure that the rest of the piece is developed enough that the focal point doesn't just seem to be floating in a void.