Neat! I like the use of perspective with the trees.
I’m no expert on composition, but if you feel like something’s missing, it’s most likely because of the rule of thirds. Grant mentions it very briefly in this part of the course; to grossly oversimplify, draw an imaginary tic-tac-toe board over your image and look at each of the 9 squares to see if it adds to or detracts from the image. Following that logic, there’s a lot of flat, open space to the right of the stegosaurus. If you put literally anything there - a herd, a different dinosaur, even just some terrain bumps or a little valley or something - you’ll probably find it scratches that itch. Failing that, you could also try adjusting the camera angle to better fill that image region with the stuff you’ve already got (I know I fiddled with the camera for quite some time when I made this scene).
I’m sure there’s also more you can do with the lighting in particular, but I’m definitely not the right person to be giving suggestions on that XD