Maybe good solution is creating no "sattelites" but high powered starbases on planet?
The problem with starbases is connected with limited slots on starbase's hull. So the starbase is not powerful station and can protect the planet again small fleet only. But starbase can be very usefull construction bacause can be equipped with special modules which can improve planetary abilities.
But how planet can be protected by starbase with limited slots? The good solution are military modules, which improve attack and defence base weapons or ships on orbit (at the star system). All weapons can have for example +10% per module, and small defence fleet will be more powerful than without base cooperation.
Starbase can be equipped with expensive special modules:
* military modules (to increase attack and defence ability for ships)
* agricultural modules (increase star's insolation at planet's dark side)
* economic modules (tourism from other planet, increase money from planet)
* technology modules (special laboratories with no gravity increase research)
* production modules (space factory)
* mining modules (better purity of planetary ore)
Or standard, cheap elements used on ships:
* attack/defence modules (to protect from small enemy fleet or pirate units)
This idea of starbases (player's design and special modules) is a fix from Stars!
.Stars! - starbase design editor
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