could you make wars just once a week say start on a Saturday finish on a sunday and improve the rewards for your score. for instance over a 100 silver hero token plus a 3 star ascension 20 gems item over 200 gold monster token and a 3 star ascension item 40 gems and 300 and above a gold hero token and a random 4 star ascension items and 50 gems. the rewards at the moment are real poor even the guild war accumulation for 25 points is poor that also needs improvement
i would love the idea of just one war a week with better loot,
maybe the warchest has to fill then double the speed, cause it could happen that you wait
ages to fill it with just one war a week.
another idea would be a 48hour war,but just once a week (12 attacks, all of your 6 teams are avaiable after 24 hours again for the 2nd round, or lets call it 1st half and 2nd half)
you have to use your first 6 attacks in the the first 24h(like now 3 attacks per 12h), otherwise your attacks are wasted, then your team is available again and you have another 24 hours.
could be fun, because after a unlucky first half you can turn maybe the game arround 
if your opponent is overpowered you at least can try some attack strategies in the 2nd half
Sounds like a decent idea. One war a week would be fine. But double up on everything ie have 12 flags run for two full days - but improve / double the loot rewards. But maybe best to have the war mid-week rather than at weekend