[QuantumDelta]

oops.....campaigns?
You can make a multi-part campaign, like, 4 missions a time perhaps.
It kinda depends on the pilots, some people even whine and scream for games then get into games and leave before the first mission is over (~5 minutes).

[kir2yar]

~ 10 minutes * 4 missions?

I think that I could not make a big company. I did one mission for about a week. : (

[The E]

Personally, I would aim for a maximum mission duration of around 20 Minutes.

4 Missions at 10 Minutes sounds like a good plan.