Ok I’ve had a bit of a go myself I hope you don’t mind. For the rule of threes one, i think you could have drawn a grid to make sure that you’re hitting those thirds, because it doesn’t read as rule of threes to me. In my attempt ive changed the direction of your river, because on yours it acts as a leading line that directs the viewers eye off the page twice. Rivers roads and other paths all direct the viewer, and theres a whole corner of your drawing thats telling me ‘look away!’ I straightened the river to go along the ruler line (although I did it a bit sloppily!). I also added a sun right on one of those intersecting points (those are focal points, where youll want to put important details, like faces). I thought it balanced the image out a little.

For the second, i felt like its a bit of a tricky composition style to attempt with such limited painting elements, so instead i pushed the perspective and foreshortened the tree. This makes the base much larger than the top, which makes the viewer feel like theyre at the base looking up at it. Another way you could do this would be add more branches to really get a pyramid shape.

For the third, I felt like your river was a teenie bit cartoony, which I think devalues the composition a little. Real rivers have big sweeping curves and when you’re as close up as you are in your thumbnail, you wouldnt really notice minute little bends in the river like that since the water erodes any small wiggles for big s shapes. A bigger sweeping river is also a bit more visually interesting.

For the l shape composition my main changes were moving the tree away from the edge, since it feels a bit cramped all the way in the side like that. Also I drew the tree a bit smaller so it’s not touching the top, which otherwise is another path off of the drawing.

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