You can always try using Man to Man defence, since we're a lower league, there aren't too many fantastic outside shooters. At least next season, they should have implemented the boxing out of rebounds, so it might improve things.
Aussie Rules:
I found that defence can be a bit random sometimes. For example you played your best Outside D against Brancati and limited him to 19 points. Yet when I played PP, I stupidly placed my worst OD player on him (he's better now lol), yet Brancati only scored 25, whilst my SG that night scored 28. Strange sometimes...
I think in general the tactic you played was just too strong for a motion offense.
I'm just hoping my injured players are back before my game with you, had 2 of my starters (SG and PC/C) injured in the last week =(