A good defense tatic is get the kick skill. so you can place the ball way in his backfield to take up his time and the cage will form later in the game giving you the chance to blitz with your WD's and not have to be in a cage to do so.
Elves can break easily but the wont always so take the chance and blitz into that cage. A WD is hard to knock down with the Blodge skills and with sidestep can get him out of the cage after one or two blocks on him.
If you are going to blitz into the cage try to cancel all tacklezones so a 1 die block is possible and use the rest of your movement to get out of there if it is possible.
you can try the one step defense against cage teams. Move at least 2 models in front of the cage and one or two to the side and one square away from his players this will mean he has to break up the cage (if he wants to move more than one square) and can only hit one of you players this turn.
Slow him down, cancel his tackle zones, Kill the ball carrier and use your high AG to Keep out of harms way.
I play DE so these are the basic tatics I use. WE have slightly less armor than most of my team but try to use tatics that your opponent wont expecet. go ful offence on one turn and beat his players down and then on the next turn keep away and blitz for the ball or injure his low AV players.
Good Luck, sometimes it's the only thing that can keep you alive
Any WE player feel free to correct any of me DE tatics. This is what I used to win my league but it may not work for WE.
remember: if you can't go around them... go through them