Outer Space Visuals

create very big sphere, and put on in star texture

Sure. There are a few ways to do it. But personally, I would highly recommend always using a skybox, at least for distant stars.

For closer stars that perhaps need to have more depth, you could always try having a particle system with no particle animator attached so the particles never disappear (thanks to 3dDude for that fix/clarification) that has its position locked to the position of your ship (sorry, just assuming you have a ship or something). They might still look distant because they're not moving, but they'll look closer than the skybox stars and add a sense of depth. Just don't lock the rotation too, or else they'd rotate with you and that'd look really weird. I don't know how this all would look in practice, but it sounds like a good idea at the moment...

An alternative to a particle system would be to use several increasingly smaller spheres with their normals inverted, textured with a transparent star map to create "layers" of stars around you.

Most space games that I know of though use just skyboxes and they look just fine (except for going into hyperdrive and things like that, where they often use stretched particles blasting past your cockpit to simulate closeby stars whizzing past). What doesn't look right about the ones you've tried?

For the particle solution, instead of making slow-dying particles just remove the particle animator and each particle will last forever. Make sure that one shot is checked though...

And what starmap are you using? whenever I have tried it has looked fine.

I believe this will help.

@Simon I guess that is my whole point. Do people think that that skybox looks good? I think it looks terrible! I've been able to replicate similar starmaps but I hate them. Do people actually think that is good?