Sorry for the long post, but I see so many people saying "plz supercell add bb clan wars to next update plz plz plz itll make game so much better!!!" but I don't think anyone realizes how truly complicated a BB clan war system would be and how infeasible it is. Here are the issues that I see:
1. Supercell is going to want to avoid making it a complete ripoff of main base clan wars. Sure you can argue that the BB is a ripoff version of the main base, but the matchmaking/attacking/winning systems of the two bases are completely different. In the main base you just need 1 star and you've won the battle, but in the BB you could potentially get 1% 0 stars and still win the battle if your opponent gets 0% 0 stars. I think Supercell would want to incorporate the BB attacking system into BB clan wars to avoid a total knockoff of the main base clan wars. I'm also thinking that a BB clan war would have no preparation day, you'd just be matched against an opponent and the war begins. You also wouldn't be allowed to scout the enemy, because the whole point of the BB is that two players are matched together in real time and only have half a minute to figure out their plan of attack. By allowing them a preparation day to get a good idea of where the enemy's traps are and the best way to beat him it just makes it too easy. There would be no attack replays either so that nobody else in the clan can see the the other clans' base layouts.
2. The star system. Whoever gets more stars/higher percentage wins the battle, but can this system work in the BB clan war? Imagine this scenario: 10 v 10 BB clan war. The bottom 9 players go head to head. Those 9 players in Clan A get 99% 2 stars on every base while the 9 players in Clan B get 50% 2 stars on every base, so Clan A has just won 9 individual battles. Then the top players face off and the player from Clan A gets 99% 2 stars while the player from clan B gets 3 stars. So that means Clan B wins the war 23 to 22, even though they lost all but one individual battle. That just doesn't seem like a fair system. And keep in mind that if you say "well we'll just ignore who wins the individual battles" then it completely defeats the purpose of the BB battle system because it's all based on the better attack, and to do away with that makes it a ripoff of the main base clan wars. So what's the solution here? I honestly don't know
3. Timing. The entire premise of BB is 2 players attack each others' bases in real time. What happens when two clans in completely opposite time zones are matched together? It's going to be nearly impossible to find a time where the person you WANT to live attack is online. And we can't say "well you shouldn't have to attack an online player" because, again, it just becomes more and more like a knockoff main base clan war.
4. Another issue that coincides with timing is who you can attack. We're keeping the underlying premise of attacking each other in real time, which means that 2 online players must agree to attack each other. Imagine this: Player A wants to attack Player B thinking he can easily beat him, but what if Player B doesn't want to fight Player A? What if Player B wants to attack Player C, but Player C wants to attack Player D, and Player D wants to attack Player E? See where I'm going here? It'd lead to one giant stalemate where no attacks happen because nobody can agree to fight. So that option is off the table. An alternate solution would be to randomly match 2 online players together. There would be no option to attack any individual base of your choosing. You simply hit attack button and wait to be matched with someone from the other clan when they too hit the attack button. The problem with this is that it would potentially lead to so many mismatches if Clan A keeps getting lucky when their players are getting matched with players from Clan B who are far below their skill level. So that option is off the table too. The BEST solution would be to force people to fight their mirrors and ONLY their mirrors. There'd be no attacking higher or lower and no random matching.
5. But another problem that arises from that is it becomes a game of chicken. What do I mean by this? Even though we already discussed the problem with the star system, let's just hypothetically say that it works the same as the main base clan wars. So to win the war you just need to get more stars or a higher percentage if the number of stars are equal. Everyone would quickly realize that they really only need to win 1 battle and the war is over. But how can that be you might say? Let's say the war just started and nobody attacked yet. The #1 of each clan fight each other and the person in Clan A wins the fight. So Clan A is winning the war now, and if they simply refuse to use their remaining attacks then they'll win the war, since Clan B simply has no way to gain any stars because they're unable to attack offline opponents. But that makes the first attack very risky because the entire war is riding on one attack, so who do you choose to be your best chance at winning a fight? Bear in mind that the highest BH levels have a lot more defenses to have to deal with than lower BH level players, so you could potentially have a better chance to win the war by having your lowest ranked player fight his mirror. This is where the game of chicken comes into play, because you're waiting for the other team to make the first move. If their #1 wants to attack but your #1 doesn't want to risk it then it's just a game of chicken.
6. Wars on main base and BB. It's probably going to burn people out having to fight two wars simultaneously. Sure, you don't HAVE to fight two wars at once but the option is there and it's likely that many clans will start to war on both the main base and BB simultaneously, and leaders don't like when you don't use your attacks. Although Supercell could potentially just prevent clans from starting clan war matchmaking on the main base if you're in the middle of a BB war, and vice versa.
7. Here's an issue that everyone should expect in a BB clan war: engineering. Will Supercell use the same matchmaking algorithm as the main base clan wars? Or will they come up with something entirely new so people can't engineer? Everyone should know that as soon as a BB clan war feature is introduced there will be plenty of people figuring out how to exploit the system just like the main base.
8. Finally, the last issue is loot. I think the clock tower nerf was enough evidence that Supercell wants the builder base to be a slow grind for us, so I don't think they would be too keen to award a lot of loot from wars. If I had to guess they'd probably award a max of 200k gold and elixir.
The whole thing just seems like more headaches than it's worth.