Hello there! 
I was bored yesterday so I decided to hop into blender and start doing some random renders. 
Feedback would be kindly appreciated. Thank you! 
Renders:
4 Likes
These look nice, I love the detail on the clothes. For the helicopter one try to add a background and some explosions.
The helicopter looks really close to the person, it’s kind of hard to tell how far and the depth of field does not look right, maybe adding a backgroud to add some more things as it is a little bland/basic.
I like the renders but if you had background and the characters a bit brighter and other things that can work too but its up to you for what you can do with the renders
Each one is unique and looks fantastic, amazing work!
I am no graphic designer so take this with a grain of salt, for the first and all renders it looks like it’s more showcasing the characters clothing from my opinion.
Although I would recommend experimenting with background selections since all the designs look like practice work there were variety of backgrounds that’ll fit the style, your wishing to achieve out of these maybe consider giving each render a proper theme since it’s related around military.
Add something interesting in each design if you can’t think of any ideas use inspiration to help you along choosing a proper background, the lighting in the first render looks a bit bright and uneven. Consider making all of your renders future similar lighting source. At the start while there nice designs i’m assuming you wanted to create this just for practice or something fun making.
Overall your renders look good you could always come back to improve them in the future.