Hey, Vignesh! So cool man! :D The thing you need to apply when drawing environments, characters or even props, is to have in mind your main focal point. Here everything has the same level of importance, and everything has the same levelof scale, which reduces the contrast between each thing. So, establish what the main FP, the second FP and even a third one. On the other hand, keep in mind the scale. Adding small human figures sells you the idea of a huge place and huge mechs. Compared to adding figures too big. Keep a better separation between the foreground, midgraound and background. Regarding adding details. Focus on adding the details in the foreground and focal points. Even the focal point can have a focal point (like the head of the mech, where you can add more details). The rest is not too important; you can suggest some textures, but avoid adding too many things. Look for artist and mimic what they do! Hope this helps!
