Gimme a sec just putting somethings together for you.
Okay so some simple suggestions to give you a few ideas of what I personally would look to do with those areas specifically.
Firstly here, I'd look to add small amounts of yellow cover in the ares marked in white. I'd look to put tracks through in the yellow circle or even a little higher in the picture. I personally would convert the whole area into a harvested field (possibly muddy) and add some haystacks and farm equipment like a tractor for some green cover (not too many items for green cover though). then I'd remover the tip of the field to the bottom of the picture and put a little foliage in there. This is just an example of what I would do to it, you can however feel free to use any or all of what I've mentioned here
Here I would run tracks through the middle of the field to break it up into two smaller areas. I would consider converting the top half into a farmhouse area with a house and barn or two smaller houses, add farm equipment a well and some wood stacks then do some kind of hedging around the areas using bushes for yellow cover. Then add some medium sized trees to the yard area. Then I'd break up the lower part of the field with a couple of craters so it's not just a large flat area without detail.
As I say feel free to use any of these ideas as you see fit. I hope I have been of some help to you on this and I look forward to seeing how you break through this. Can't wait to see the next reel of screenshots.
Kind Regards,
Mirage357.