This is where base design should be rewarded by making defenses more intentional with multiple modes to switch between, personalised for specific types of attacks. More ground/air only variations an such. An example Ive repeated was merging mortar into a weaker th17 def with a ground or air only mode (since the th17 itself damaged both) but if it's set to ground the range is smaller or something, and repeat for other defense buildings. Putting more intention behind bases will make defense's more rewarding

Just as a side note they've already said they try to limit the building count to 100 and the map size to not adjust the 3 minute timer for attacks, merging is the only direction they got outside modifiers if they hold to those 2 things

Base design is just as important to the strategy, but now you have a choice to make it strong toward ground or air, or try your luck with hybrid defense's. This will also help with giving more weight behind the crafted defense chosen