I say turn the tables on THEM! The penalty for letting the enemy get too close to your base is that it runs the risk of getting temporarily flattened. To protect your base, you have to push out and defend forward. Keep the enemy at bay so your buddies can get up and back into the fight. That gives both teams the motivation to at least meet in the middle. It would remove the idea of "hey guys, lets fall back to the base ack and let them come to us!"
IMHO,
Wab
And this is where we don't have common ground.
Motivation.
Trying to devise game mechanisms to force players that don't relish the fight to get into the fight never really work IMO.
OTOH, there's no point in playing if all you do is fly around.
Imagine this Wab: What if no one pursues to the field? What if everyone stayed within a mile or two of the trench line on the map that divides the two "countries"? Where would the fights be then? If all the action was over that middle trench line, how long would a player stay in the ack at his home field?
It's the old deal from early AH where you let the guy get up, get some alt and get some speed so he could have a reasonable chance at successfully engaging rather than getting slaughtered over and over again. In pursuit of score, that ethic has pretty much disappeared from AH. That ethic makes for better gameplay though.
To me, the 'cheese' for the mouse is the fight itself. If a particular mouse doesn't like 'cheese' you can try electric shocks to move him through the maze but now instead of joyfully going to something, he's just trying to avoid unpleasantness and will try other methods to avoid same. The latter doesn't make for much of a game; see the WW2 MA.
IMO.