Hi!
Proposed flyer system to integrate with Bissler-geddon
We at net epic has tons of experience with alternate flyer rules. We have been added, then removing such rules since net epic was born.

With a combined activation system it presents great opportunities to revisit old ideas.
Point one
We learned from the past to place flyer missions in its own separate phase. More importantly we learned to place that phase LAST. We tried putting that first (very bad mistake, especially on turn one) and in the middle it didn't work out that great.
Leaving it before the end phase clean up worked best.
Point two
While I understand that by scale, a flyer should be able to come in, perform its mission and leave the table in one activation. While it is realistic it defeats the purpose of having nicely painted flyers on the tabletop. Why have them at all if they cannot be seen and interacted with?
Due to this we'll keep movement rates for fliers, to keep them "visible" and enjoy them.

Point three
We like the three order system. So we keep flyer missions to three as well. You can use the same three counters (first fire, advance and charge) or make new ones. But we kept them at three.
So with these three points as guidelines we propose the following:
The "air missions" phase occurs after the assault phase ends and before the end phase.
Flyers move from their sides deployment zone into the battle area. Fliers may not use entry zones (they always start on their own table side).
During movement any units with the anti-aircraft ability may fire at flier formation within range. Hits, armored saves and casualties are taken immediately. Units that take at least one casualty of AA fire must roll a morale check to continue the mission. Only ONE such check per turn is taken regardless of the casualties taken.
A given unit with the AA ability may only fire ONCE at a flier formation during a given turn.
Once flier formations enter the airspace of the game table they remain on the table. If they choose to leave they may not return for this battle and the opponent receives half their VP value rounded up.
Fliers may be given 1 of 3 orders:
Strafe/bombing (advance order): A flier formation with a strafe bombing order may move and shoot any or all its weapons during any part of its movement. Note that it may attract AA fire from AA capable unit at any point of its move.
Defensive formation (first fire order): flier formations with this air mission may land if capable to do so and unload their transport cargo. Any flier formations that try to intercept a flier formation on defensive formation will first withstand defensive fire of the units (they may fire all their weapons ONLY at the interceptors). The survivors may them engage them in aerial dogfights. Units capable of AA fire will receive return fire from surviving units with this order (all weapon may fire upon AA that has fired on them). Formations with this order may not fire at any units with the exception of units trying to intercept them or AA units that fired at them.
Interception (charge order): Flyer formations with intercept orders, seek out other fliers to engage them in close combat. Since they are not seeking to engage ground targets they impose a -1 penalty on all units capable of firing at fliers (AA units). Once the interceptors have engaged they will fight an aerial combat round.
Aerial dogfights.
Dogfights are mean business. Once a round of dog-fighting is over the formation that lost the most models has to roll for moral. If it passes another round of dog-fighting ensues. Continue until one side has been eliminated or routed.
If the losing formation fails its morale roll the winning side may fire all its ranged weaponry as the loses breaks from the dogfight. If any units survive, move those their full move to their own table edge (AA fire applies). If the flier leaves the table it is removed from play. If it doesn't leave the table it may attempt to rally in the end phase.
As ground units they follow the single/combined activation (move and shoot).
We could include some "abilities" for fliers:
Interceptor: incoming AA shots are at -2 instead of -1.
Flying fortress: Defensive fire receives a +1 bonus
Skilled bomber: Re-roll misses on one weapons system.
Thoughts?
Primarch