Does anyone know if losses affect the missions and or planes? EX: If a mission is flown with heavy damage/losses, will the old planes be pulled out for the next few missions until repairs/ replacements happen (to the front-line planes) or does it just reset?

Some how missed this one. Planes shot down are shot down and you have to wait for replacements. Planes seriously damaged I believe can be out of commission for a while. There have been times my Jasta only had two flyable aeroplanes (actually there have been timers I had no flyable airplanes, but that induces a bug that requires either reinstating your pilot's previous mission/game save, or a bit of hex editing to fix.