One of the main reasons for the time limits was to prevent players from jumping back and forward to the enemy side, look at the radar, listen to the buff pilots and then jump back and bounce the bombers en route to a target or slap down a C47 in field defence.
No one does this and even if they tried to do so regularly, the one hour limit would make it very hit and miss. And you can already "spy" with shades and/or friends on the other side anyway.
Here's a genius idea: Make your objective dependent on FINDING a flippin' fight instead of avoiding a fight and "spyz" won't be able to do anything to you.No time limits can also mean jumping back and forth to see what the enemy radar situation is like. Wouldn't you like to know if their radar is down without having to fly all the way over there and look?
Or you could just look at the flippin' map and see what enemy radar circles on the map are red instead of white.

Anything less than an hour will mean buff missions as in jepardy because that's about how long an organised attack takes to complete.
If your plan is to waste more than an hour of your precious lifespan on a buff mission, the guy who shoots you down is doing you a favor. Go outside, pet a dog, or if you stay in the game at least you might grab a beer and up a fighter to get your revenge on the bastage.