A fighter skirmish should not be worth the same as Border battle. While both battles do win the same amount of territory on the game board, the tonnage and souls lost is on a completely different scale. To keep things easy, I suggest something simple like this:

Battle 12 Points (battles only show up once a week).
Large 8 points
Medium 5 Points
Small 3 Points
Fighter 1 Point

+1 Agreed Why would a side put in a huge amount of work on large skirmishes and on the flip side the other side can win like 5 easy fighter skirmishes and put all your hard work to rest?