Maintenance nearer to real life costs and personel shifts.

[11Air]

So, the game has scheduled maintenance times that lock out any flights that overlap them, so often the maintenance crews are working on more than one aircraft occasionally, so:-  I suggest that the number of employed maintenance crews required should be assessed, and charged to the airline.
OK, a minor issue, I know, but the rest of the game is very well organized, and even with a small fleet, as the fleet grows then demand for maintenance teams also increases. And scheduling them in, for larger fleets, should allow for either night or day shifts for each crew. One crew not able to work on more than two shifts in a row, and not more than 5 days a week.
And additional hangers etc for the major maintenance issues!
And maybe aircrew, pilots and cabin staff, should also be limited, and this could be a hidden (in game decision) based on a bit of of maths in the game mechanics that decides when more staff for these particular issues are required.  Real world there on extra staff on board for long flights, so crew, cockpit or cabin staff, can be replaced as required by the airline regulations, and the union regulations too i guess!  But the cots to the airlines are very much a real thing, and the cost of recruitment of their staff too, are also a cost to the airline, even if it is often done through agencies, or by the companies office staff, and interviewing too all adds to the airlines costs.  Minor factors maybe, but your game is pretty good, these little tweaks might make it even better!!!  Doesn't need all the detail I mention, but some tweak to cover these additional costs, based mainly on the size of the fleet maybe, and of each aircraft type too, and bumped up again where the bigger airlines operate from more than one base! Perhaps. Where office and maintenance staff would be based!
Or, maybe you've already included those features?

Love the game!  So good already!
     

[groundbum2]

have a look at office/personnel.

For flight crew the overcrewing is already done. For example schedule a SMALL plane and 4 extra pilots are hired,  8 for a medium, 16 for a large and 28ish for a VL. Something like that.

I would expect the same for other job descriptions.

The only thing that isn't modelled is maintenance staff being hired to cover the peak period, eg Saturday, when most maintenance is performed. So there's no invemtive to spread maintenance through the 168 hour week. Although 7 day scheduling does this as a side effect.

Simon