i take your point, air dominance is the key. but it shouldn't be so over powering. things will get so boring otherwise. i think there should be some mechanism where only using air attacks wont get you 3 star on any base, maybe something else than what i suggested could help for this cause.
The bigger picture here is that it will make attack and defense more interesting and more skill oriented.
Only havung the DE stirage be unaffected by air troops isvery unorthodox. Having it at least be immune to lightning spells could work, but limiting the freedom to raid with what we want will lower the ratings on the game. This games porpoise is to let US pick a strategy
No. Lighting immunity is ok but mass dragging is the only other way a TH7 gets DE. Loonion is the main De farming method in the higher leagues so it will be useless