personaly I go for 30K+ cloak, like on this one
basickly just
Passive Ability - Cloak 4435
+
Ergosphere Filter (size 1, Cloak: 150, Cloak: 20%)
Meta-Tuned Jammer (size 1,Research: 2, Cloak: 25%)
Polaron Emitter (size 1, Research: 1, Cloak: 100, Cloak: 15%)
Ryelis Analyzer (size 1, Research: 2, Artifact: 2, Cloak: 5%) -(mostly for the size 1, artifact 2, but the cloak% bonus is also nice)
+
Isolation Bureau (size 2, Mining: 2, Research: 2, Artifact: 2, Cloak: 400)
Adumbrate Station (size 1, Research: 2, Artifact: 2, Cloak: 400)
Adumbrate Station ( size 1, Research: 1, Artifact: 1, Cloak: 200) - proberly the next one I upgrade
Silthion T-Plasma Vesicle (size 1, Research: 3, Artifact: 1, Cloak: 300)
Shrine of B'elna (size 1, Artifact: 1, Cloak: 300, Bonus Artifact: 2%)
Scruuge Calibration Chamber (size 1, Mining: 1, Artifact: 1, Cloak: 400)
2 * Litheor Deep-Phase Probe (size 1, Mining: 2, Research: 2, Artifact: 2, Population: 900, Cloak: 150)
2 * Quantum Accelerator (100% Upgrade) ( size 2, Artifact: 4, Cloak: 300)
2 * Klorvis Shroud Generator (size 1, Research: 1, Cloak: 200)
2 * Sha'jha Uplink (size 1, Research: 2, Cloak: 120)
I might replace the Klorvis Shroud Generators and Sha'jha Uplinks with a Nexus Spy Fortress (size 2, Research: 8, Cloak: 600) - if I find some more artifacts I can put on the planet to increase production
and the Ergosphere Filter will proberly also be replaced by a Corrupted Edifice (size 1, Artifact: 1, Artifact Storage: 2000, Cloak: 20%) soner or later
and ofcourse, once I get it to Passive Ability - Cloak 7500'ish I can proberly lift the Meta-Tuned Jammer and still have 30K+ cloak on planet
but every structure I used to cloak it, exept the Ergosphere Filter adds production, and most of them even artifact production