With regards to the mass-for-mass efficiency of ADF vs ASF, I don't really think it needs to hold true. You likely need to make each ADF fighter unique to each faction due to how each faction's ASF output damage, but the point would be that it allows for asf to kill singular fighters quicker without doing "useless" damage by leaving ASF on 10 hp and requiring yet another shot anyway.
Something easy is the UEF ASF since it does 400 damage in a single volley basically. ASFs range from 2450 to 2600 HP. The goal should be to at least allow UEF ASFs to kill in 6 volleys rather than 7, meaning the UEF ADF needs to do at least 200 damage over some large area.
Now ADF fighters would also have a significant reload time, meaning that if you just spam them and hope to crush ASF, it would only work if the enemy flies a gigantic blob of ASF at you and you get to freely do the necessary damage. However, if the enemy just sends 3 ASF followed by another 5 or something similar, then you just get crushed no problem.
Likewise if they have low hp and low speed, it is really difficult to just lose a few and then go and replace them from your air grid. Air becomes a lot more about sniping the ADF fighters to then allow your own ADF fighters + your own ASF to win a crushing victory rather than just building up giant blobs of ASF until an air win is necessary to win.
You can even make ADF fighters pretty expensive so sniping them in general is just a big win for the other guy.
All of this causes smaller groups of ASF to serve some purpose rather than just being easy targets to kill with your own giant blob. A successful small ASF attack could be what allows 100 ASF to beat 130 ASF or cause the 130 ASF to retreat while you get control of more of the map.