This is a good video to get the feel of American indoor soccer
http://www.youtube.com/watch?v=ly0g2C3Wn-c&feature=relatedAnd I would make the ball look like this
http://lavacafe.com/PAGES_SUB/TRIBUTE/STAMENKOVIC/ball_voit_misl.JPG -- with no writing on it.
The grass should look artificial, not like real grass both in color and texture
In fact maybe something like a goalie diving to make a save and Indoor Soccer Hall of Fame on the boards next to the goal like in place of where it says MISL in the video.