This is my first post here, but I'll try to be brief and get right to it. I have skimmed the forum and I have not seen the suggestions I want to make, but I cannot be sure that I haven't missed them, so please forgive me if I'm repeating what others have already wrote.
I've been using the program since version 0.9.7.3 and I admire the scope and the detail. With a new version on the way, I wanted to point out a few things that I'd love to see implemented/improved.
First of all, stars and galaxies very often hit certain size limits. For stars, it's the 300 solar masses, for galaxies, the 100 kiloparsecs diameter (and very often the 3.5 trillion stars number pops up for spirals). I think more variation could be achieved, and while there is no problem with upper limits that would prevent stars/galaxies to be rendered at impossibly large values, I suggest a second order of randomization of say 10-20% around the already determined size could result in a much more realistic universe.
Secondly, the cube shape of the universe seems to me somewhat odd. Would it not be possible (until an infinite or torus solution is implemented) to at least have a sphere with the radius of 46.5 billion ly (the generally accepted size of the observable universe)?
Thirdly, I was hoping Space Engine could be made more didactic in nature by allowing some leeway over what's rendered.
For starters, would it be feasible to input absolute magnitude cutoffs for stars/galaxies? For instance only stars between Mag 4 and Mag 10 would rendered, with the user being able (like it is now) to increase apparent magnitude limits in order to see those further away.
In the same vein and in conjunction with the above, distance cutoffs would be great. It would allow users to only render stars/galaxies up to a certain distance, so that they could simply explore a region of space with no regard for the rest. Rendering could be done continuously as you move through space (a sort of comoving distance), or only once from the point of the camera, and then stay fixed for you to fly around it and explore.
As such, there should also be an option to limit the number of stars/galaxies rendered, so that the user could prevent an overload and a crash of the program, with certain rules determining what's shown in case the number of objects meeting the selection criteria is larger than the number of objects that the user allows to be shown at the same time.
And finally, in the same 'didactic' category, SpaceEngineer explained that galaxies are rendered in filaments. Does the program know which galaxy belongs to which filament? If so, would it be possible to have only the certain filament rendered at once? As it stands, the macro structure of the universe is lost on us.
That's about it for now. I'm very curious to see opinions on these suggestions.