Very nice. I used your edit as a reference and updated my version appropriately(see modified opening post). The duck does really look more ducklike now. I still have to work on the arm and hands of the chicken again though, as it looks not very satisfactionary to me.
I don't know about the chickens feet in the back following the perspective, because they are so tiny, it might not work. Horizontal line will translate more smoothly into the hills when I get to coloring, but for now, I'll keep it and:
Hope that this is helpful. Post came a bit late, i know 
Yes. Thanks a lot, it is very helpful indeed and regarding it coming "a bit late", no problem, absolutely no problem, your time is probably as scarce as mine, so again thanks for taking some of that time to help me. Besides, I don't believe in speed(see my sig).

What's next? Well, I showed Andrei this thread and he suggested these things, which I'll work on next (after fixing the currently bad hand and arm of the chicken in the front):
- There should be more pipes. Chickens is a game about junctions of
pipes. There should be at least one pipe-interchange visible. One good
place to add more pipes would be the inside of the barn (eg. the black
bit above the haystack. Another place to add pipes is the bit towards
the back just before it becomes a hill. Drawing pipes in the distance
means you don't need to worry too much about the detail. - Two dancing chickens dancing with eachother near the chicken-party
- Perhaps more instrument-playing Chickens. Johan(is making music for the game) could suggest which instruments to use. One possible instrument is a double-bass.
- There should be an extra dive-bombing duck just behind the one
carrying an egg. Of course, it is OK to clone the downward-diving duck
to save you some time.
Not sure, where I will insert the dancing chickens or the additional instruments as there isn't that much room left to fill, but I'll see... (maybe the double bass chickens could sit on the barn).
Btw, the game itself is freeware and you can download the current version from the page, linked to in the opening post, if you're interested in it.