Satellites - maintenance cost.

In my opinion, no, satellites are not overpowered for a couple reasons:

1) You have no control over their position during combat, they clump in a single sector, and they can't move. They are just as likely to be out of range on the opposite side of the planet as they are to be facing an incoming attacker.

2) There are limits to how many units can be launched in the same sector, and how many total units can be launched throughout your whole empire. Both of these limits can be changed in Settings.txt , but I've never seen that make a big difference in how they're used.

I think fighters might be slightly stronger than satellites, since they're mobile and can be kept on the planet until needed, but that's balanced against them being smaller (with shorter weapons range and less damage).

"Good morning, Pooh Bear," said Eeyore gloomily. "If it /is/ a good morning," he said. "Which I doubt," said he.

i tend to agree with capnq

you can also build fighters on planets without shipyards

early game satellites are a really good way to strengthen your defense on the long run i dont really use them...

I tend to use lots of satellites, but not so much in orbit around planets but as blockades. I build some ships the deploy satellites and lay them, about 20 at a jump point. They will ALWAYS be right next the point in the tactical combat, and if they don't destroy an attacker they weaken them. Paired with a ship or two, it is a very good defense. Better than mines because they only need relaying if they get destroyed. Mines I do find useful around a planet though.

Fighters work better in almost every role satellites can be used for (except as sensor buoys).

How does this have anything to do with maintenance cost?

I like sats around warp points, a mega pain to lay, but they can last all game. Esp once you get a shield on them, and then put a repair bay ship in the hex with them.
Let's go

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"Good morning, Pooh Bear," said Eeyore gloomily. "If it /is/ a good morning," he said. "Which I doubt," said he.