Not sure if there is any purpose for the large open areas of woodland/green spaces yet, but I found myself wandering through that area as I was unsure which way to initially turn outside the house. Maybe I should have read the controls to see there is a map to be fair ;)
Health and weapons etc could be increased in size just seems to be quite small for me anyways.
Also the grass areas are just one colour it seems so some tonal variation or random shrubbery would make it look a lot more detailed and less samey.