I don't know if this has been suggested before but I have an idea on how to address the excess elixir at TH8. Make Level 9 walls available at TH8. This way the cost per max wall at TH8 would be 1.5 million and 3 million for TH9. It will also help balance the gold/elixir cost at TH8.
Since players will have to wait until they have 1million elixir before being able to dump it into walls there would still be loot available. Thanks for reading and comments are welcome.

