Pls read this,

clan war tournaments
clan war gambling(like who will win the war,u bet for one side with gems,and if u win ur gems get doubled,e.t.c)

add mini games

ending war if both sides have used all of there attacks

NO draws in war,u can have the leader battling each other or the top guys of the clan to attack,and whoever gets more stars win,or even let d leader choose 10-10 players to battle,with a specification,for eg- 1 th 10,4 th 9,3 th 8 and 2 th 7.
War donations count as real donations,but the guy who requests can select wat type of troops it want and dere lvl(for eg - he chooses wizs,witch,pekka,mins,valks,and chooses the least acceptable lvl) it will encourage more players to donate,so a guy doesnt end up donating and getting no credit.
An offline mode in wich players can use coc,but only for single players,like goblin maps,trainin troops,e.t.c
Add more lvls in goblin map,and u can even add more maps,like barbarian map,archer map,e.t.c(each map getting tougher)
daily rewards