My solution to spying and engineering
Spying:
Create 1 more rank in clans in between elder and member called warrior. This position would have same benefits that member currently has. Member would be allowed in clan, able to chat, but would not have access to view war bases. That way all the constantly warring clans would be able to recruit without worrying that someone is trying to cheat them. Just do not promote anyone to warrior until you are comfortable with them. Spying is now gone.
Engineering:
Town Hall penalty in War
For every level Town hall that you 3 star above your current Town hall level you gain an extra star. This would stop people from building defenseless bases. These bonus stars would only be available for the first 3 star on any base and only if the base is 3 starred.
If TH8 attacks defenseless TH11 and 3 stars it = 6 stars for clan.
If TH9 attacks defenseless TH11 and 3 stars it = 5 stars for clan.
I know it is severe but it would make people defend their base not just sacrifice their villagers. We are supposed to be their chiefs, right? Doesn't that mean they are trusting us to defend them?