Oh are you getting better isn't it? In the first one the value separation is almost ok, look at the background, the values are too dark to be that far cause there's a lot of fog between the rocks and the spider mech so they read as they're close messing up with the composition!

The second one i so messed up that i don't know where to start... Nova you should start up your drawings with 50% grey instead of black, it will really help you.