Take twigs clear night or some open map like that, shrink it down a bit... and make the goal float more in an open and higher area... with like 3 seperate blocks that are angled toward the goal above and kind of behind the goal and then create some sort of a keeper platform that is floating higher up as well...
dunno if u can get my idea from what im saying but i think it might turn out kinda hard and unique, you could take out the blocks for a non-vo map.. but who plays non-vo anway ,
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a second idea... is like inph was saying those goals from pitfall however make the goal register when the ball gets to the bottom of the goal... that way if someoen hits it against that back part and it bounces back into play then it doesn't count.. this would require more of a skillful shot... just put that in whatever looking map...
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last idea for now is to put two goals facing away from each other a players height above where the ball starts, create the goals, then platforms for keepers and make an open area on either side, end | goal1| ball spawn |goal2 |end kind of thing.... that way they are facing away from each other and its just another place to put the goals , but might challenge players and provide some new game play...
I dunno how to make maps, other wise i would have tried theses

anway, ideas are welcome , hate is welcome too since i know you all love me.....
-butt