The only good "trick" I'm aware of is getting Phasic Cloaking (max level), parking the Jikara at a star, turning off autocast on everything, and activating Phasic Cloaking.

At the max level, Phasic Cloaking consumes 2 AM/sec, but at a star's gravity well, the scout will also regenerate 2.5 AM/sec. So, you effectively have permanent vision of a star's gravity well until you pull the scout.

Don' forget the high level phase detection that the Vasari get.  Once that is enabled, no fleet will be able to surprise you.

there is a way to place remote sensors with vas but it is extremly risky. the maruader has the sabotage ability and in addition to slowing production on a planet it also places a sensor on the planet. marauders are hard to catch too, with their speed boosting and anti-pji ability. but of course placing sensors with a cap is always risky as it requires large amounts of anti matter to jump in, use it, use the speed boost, and jump out