I have dealt quite a lot with the sizes in Oolite, there is only one factor that is unrealistic
Distances and by that the size of planets, and all the derivative factors that depend on these...
The small distances was set to counter the feel of an empty space, since the Oolite universe is dynamic. It would be empty because at the same time the author had to take into account at what CPU level he wanted the game to run on..
But along with larger sizes and distances comes the dreaded precision problem, that starts to show at around 7,000,000 Oolite km... A factor 20 planet is a planet of 60,000 standard Oolite km / multiplied by 20 = 1200000 Oolite km. Or 1,200,000 Oolite km or 1/14th of the entire precision stable range...
Precision means, the better the precision, the further from absolute coordinate 0,0,0 are ship rotations / movements /effects calculated and thus displayed, the further away the more you take note of these inaccuracies, at 7,000,000 the become notable... at 15,000,000 they become extremely notable... at 50,000,000 the game engine begins having trouble even propelling a ship in certain directions... Effects such as flashers etc etc... will become extremely inaccurate, in fact they will rotate into your forward view screen if your ship are carrying any such as the shady cobra.. exhaust plumes will look shake... lasers all jumpy... and much more...
I´d say instead of making this a one or the other way decision, that it should be an option.
Realistic distances on/off
Realistic sizes on/off
Standard Precision or
Best Precision
Things to take into account in order to achieve this are
Alter Planet Mass-lock (easy)
Coordinate System handling Old system vs New system... (hard)
Non-fixed position for Witch Space Entry point (call it a floating witch point) (easy)
All below (hard)
Hard-code wise, what containers to use in order to obtain this better precision or the complete replacement of Oolites absolute coordinate system that is used the OpenGL drawing functions...
There are ways around these precision problems, but none of them comes without a performance hit...
My own personal best bet on order the solve the precision problem would be
1.- Use Oolite´s current Coordinate system for the user to plot and retrieve coordinate information, this will keep it backward compatible with older OXPs
2.- Design a new internal coordinate system,to be used by OpenGL only and only when the user has selected Best Precision as this will cause a performance hit.
3.- Design a translator between the Internal coordinate system(OpenGL) and external Coordinate system, used by the user to plot where to spawn ships...
4.- Recode Oolite´s handling of to the player distant objects.. objects you can´t see do not need to be drawn. The stations for example are visible from very far away.. keep only their position/heading/orientation/ and current actions. For distant objects collisions should be handled with simpler calculations... For docking figure something clever..
5- Design a method to move the internal (OpenGL) coordinate system around the player once he begins to leave the stable range.... while not moving the external coordinate system.
(my solar OXP is using just such a method, where all ships are moved out and in of the stable range coordinates... it affects the non player occupied systems though...
My reason for writing all this... I´m trying to explain why it is just not so simple upping the sizes and distances.. everything above is my own personal opinion about what is needed in order to make planets & distances more realistic.. Oolite was never designed to show the real size of planets as its heritage is Classic Elite..
In order to get realistic sizes and distances, a near complete recode of Oolite would be needed...
just my 2 cent...
