Sawyerstooth, aren't you also destroying teams that are 6k-10k "power" more than you?
It just seems to me that it's the nature of the game right now that you can take out higher than you and be taken out by lower than you.
Don't expect a viable defensive strategy, but if you find someone else who you can't beat that you think you should, figure out what they did. If you can't take out teams 6-10K higher than you, then it's worth figuring out why not.
Huatimus gave good advice.