may I ask what is the purpose?
do you want to use a sextant for navigation?
Actually there several things parameters:
1. The sunset/sunrise speed - how much time it takes for the sky to become clear. Makes good appearance for SEA for example flying at north areas with lots of sun but close to the horizon.
2. The location of the sun isn't always 90/270 so if you takeoff W/E you don't get it directly to the eyes
3. The shadows would be much more natural - i.e. the sun just above you at 12:00 almost never exists in real life especially in the areas were WW2 was.
Now, It can be implemented quite trivially (two new parameters for the arena and simple equation update for the sun location) and would improve the impression at SEA.
I would also add non-standard atmosphere - for example in Hot areas (North Africa) the performance is very different the aircraft performance at north.