Balancing TH6/7 Air attacks without breaking anything
As you all know, Dragons are completely broken at TH7 and balloons with heal spells are completely broken at TH6. Nerfing either of these troops would make them useless at their respective town hall levels, so I have a different solution.
Archer Towers
Level 9 should be available at TH7. Level 8 should be available at TH6. Level 7 at TH5, so on and so forth.
Hidden Teslas
Level 4 should be available at TH7 and one should be available at TH6, able to be upgraded to level 2.
Air Bombs
TH6 should be able to get level 3.