Hi Marc
Great response and do think the rules in your case are doing much more good than harm. Nobody likes restrictions but in this case, they lead to better photography and enjoyment.
Regarding the clean bg to showing more nature background, sure happy you brought it up. It seems that images without a clean bg and everything perfect are perceived as point and shoot or lesser images.
They are actually two totally different types and can be good/bad all on their own. The clean bg etc, are easier to make since all you have is the bird or animal etc. The others, I call environmental images and are some kind of difficult, if you want to have one work. They have so many elements and all have to be dealt with, if you don't ... then it becomes a point and shoot type image.
I try making environmental type images involving birds and wildlife, don't have as many as I would like since the keeper rate is rather low. Just posted one for curation which I feel its a beautiful image, worked long and hard to get the perfect blend but is doing poorly. Imagine there is a strong affinity to equate a bird on a stick with quality. Again, some birds on a stick can be beautiful, just look at one just published by Greg, a thing of beauty.
Anyone that can add to the clean vs habitat bg please do. Might just open a topic to see what the feelings on both happen to be.
al