Yes, they are good.
but i think they are just "sketches", you need proper materials, maybe a canvas..
colouring in crayons will never get you far.
I also think you need to take a look at the pictures, there is alot happenning but there can be TOO much.
And you need to scale the pictures properly..
and think about the fish you put in the ocean - most of those fish wouldn't be in the same waters
and i dont understand why you have planets in them all. stick to one topic!!