Change war completely
Just like everything else in the game, make a tier system of difficulty. But !! Let the ally choose the tier at the beginning of the season. Epic, master, heroic, normal and beginner. Different rewards for each at the end of the season. Rewards are much better for epic as opposed to heroic rewards, and so on.
And instead of matching you up against alliances with this war rating system, it matches you up against alliances with similar win/loss ratio.
The first matches will be absolutely random. Second matches will be random for the people with the same records. So eventually there will be alliances who are 5-1 competing against each other, and so on. And If an alliance goes undefeated, the win, obviously.
Points will be scored the normal way during matches. These points will be used to break ties.
At the end, undefeated alliances when prize A. Once defeated win prize B, twice defeated prize B, and so on