Note: This procedure requires editing a game file; creating a backup copy of the file before proceeding is recommended. With a text editor, edit the .cfg file that corresponds to your player in the "base" folder in the game folder. Find the "seta g_secretCount" line and change its value so it appears as:
seta g_secretCount "70"
This sets the number of Golden Starships found to 70, which unlocks all completion bonuses.