It is a good game, BUT add. In your next UPDATE,  Please do the following, this will make the game more realistic; 
(1) Add advanced engine system with start up, faults and fire suppression 
(2) Add Anti-Ice system  (DE-ICING)
(3) Add malfunctioning of flaps,  rudder, air brakes and rudder
(4) Add failure sensors,  Instruments, ASM, Engine ON/OFF
(5) Add advanced Instrument Landing System  (ILS) and Navigation display, remove checkpoints 
(6)Add Hydraulic faults,  tire problems 
(7) Add wind turbulence and fog with various levels of severity