Warppoints are always visible, otherwise cyan and red storms would be inescapable deathtraps
Make it a sector cloak on the asteroids; that will hide everything except warppoints (even planets)
In settings.txt:
Code:
Empire Base Planet Mineral Usage Rate := 2000
Empire Base Planet Organic Usage Rate := 2000
Empire Base Planet Radioactive Usage Rate := 2000
Adjust your spaceyard ability amounts to match, of course.