We still want our heroes in wars!!!!
I was really disappointed to see that the hero problem in wars isn't covered in this update. Hero strength is considered when match making but in the actual war you cannot use them?!
To be honest I doubt that this is a technical issue, it's rather all about selling gems and your revenue. The Clan levels are just another incentive to buy gems and awake your heroes. So as long as you don't release the heroes for wars you have to find another solution to balance the game. You can see easily that this is the most requested feature and almost all Clash players agree: WE WANT OUR HEROES IN WARS!!!!
So I think there are only a small amount of solutions for this problem:
1. Leveling heroes without waiting time until a certain level, e.g. you can upgrade them to level 25 without waiting time and after that you have to wait or buy gems. Right now it's too expensive to get your heroes up, just to reduce the waiting time you have to pay like 700 gems each time (level 15 heroes and up), so this is an easy equation:
25 LVL*700 gems = 17500 gems. For both Heroes this is 35000 gems which is much more than 200 USD/€. And in this equation the cost for D elixier isn't even included.
2. When hero is upgrading consider this while searching for an enemy. As you can't use your hero for offense this should take effect in the matchmaking process to get an adequate clan war enemy. The upgrading hero needs to be blocked for the war to prevent gemming once an enemy was found.
These two options could be technically challenging but it's definitely not impossible. So please SC do something about this problem in the game because not everyone can afford to buy gems for every upgrade and it takes a lot of fun out of the game.