The "capture enemy plane" mission proposal gave me few ideas for flavour missions... perhaps to much flavour, not sure how workable they are. (Oh, and please merge the threads if you believe it shouldn't be separate discussion). Both are situational so they may be unintended ways to deny them to enemy, or abuse them.
Drop the package (wreath/ message). There is lots variants of how it can work, I'm including them all so best one can be chosen.
Done historically many times before 1917, this will suit best early missions. Your side has either killed an enemy pilot, or brought one down alive and captured. Now, either you've decided to drop a memorial wreath on downed pilots airfield, or hospitalised enemy has asked you to drop a letter to his relatives on his field. The intelligence officer decided that it will make good propaganda piece and the flight was quietly approved.
Your side killing an enemy pilot dead, dead, dead (wreath variant)
Enemy pilot ending his flight alive, on the ground, behind your lines (can this me detected in mission?) - message variant. (Weaker, because enemy pilots may kill themselves to prevent triggering it?).
Mission: The package plane - a special single or two seater carrying the package must go over enemy airfield at low (1500-2000m) altitude, fire 3 red flares to bring attention to himself, and wait for message "wreath/message has been dropped", then return safely to his home airfield. The journalists and observers from neutral countries have been "accidentally" ferried in to interview them, there is even camera to make movie of his landing, and propaganda value will be lost if he ditches in the field!
There may be simpler "two wreathes" variant, where both sides get this mission when their kill their first enemy and both score 1 point if their package pilot lands. Or there can be "one wreath" variant, where the first side to kill an enemy gets to drop the wreath, and other side gets their point by stopping the wreath plane from returning home (so, if the wreath plane takes off and lands he scores a point, if he gets downed or gets lost or runs out of fuel enemy gets the point). The first variant is simpler and less likely to unbalance the game.
Rescue a downed pilot
Your side is doing badly, and now a skilled pilot assigned to special mission has been brought down behind enemy lines and is either captured or hiding. You must bring him back for sake of morale.
This is inspired by movies and accounts to numerous to count - a pilot landing next to downed comrade to bring him back has almost become a cliche... unless you do it yourself . But it was done historically, JG1 itself was sending search and rescue missions when MvR went down behind the lines, until his death was confirmed. A variant of spy mission, meant to give something to do to side that completed or busted all their missions already, and salvage some points!
Triggered by: Your side losing both specialist planes of one type before they trigger all possible objectives. You have no spy planes to pick the spy, or picked the spy but failed to bring him back and/or inpect the area he points to, or lost both general planes without capturing him, or lost both recon planes without completing the trench map. Anyway, a multi-points mission is a bust, some targets can't be activated.
At this moment, one of your lost pilots is assumed to be behind enemy lines (there is no requirement to actually lose one, we should be encouraging people to try and go home, not to get captured to trigger missions). You can go and try to bring him back, and win back one point if you succeed. This mission only triggers once, regardless of how many other missions you have busted , and it cannot bring your score over 12. If your side is doing well, it is never triggered! It is meant to give a losing side something to fight for in endgame, and another chance to bring their score closer to 12.
There are many ways to implement this mission... either look for flares from downed plane (clone of spy mission), or look for prisoner convoy (clone of general mission). Here is maximalist approach for long and interesting mission, it amy be made simpler by cutting parts away.
-Rescuers are given 3 locations on the map (chosen from named "objective villages")
-One of locations contains downed plane. There's 50% chance that pilot is there and flaring, if so, rescue plane must land within 3k to pick him up.
-If pilot is not on plane location, rescuers are directed to prisoner convoy at a named location.
-Convoy consists of open topped guard tracks and closed topped prisoner truck. Guard trucks must be destroyed before rescue is possible. After guard tracks are destroyed the prisoner truck halts, and rescue plane can land in 3k to pick up the pilot.
-only special rescue plane can pick up the pilot. His side scores one point if he lands on friendly side, or if he is still flying at end of hostilities, after picking up the pilot.
-for extra flavour: if rescue plane lands on friendly airfield with a human gunner, that gunner has death/capture penalty removed.
All locations are known to rescuers and other side is not informed of the mission - if things have gone so far that this mission is in play, the rescuers are racing against the clock already. Of course, if defenders notice a downed plane that does not despawn at named location, they know what is coming...
Of course, we can just have "strafe convoy and rescue prisoner" mission as alternative to spy/general, without all the fuss described above .