Well, I guess I'll weigh-in on this one...
Asteroids
should not respawn; however, there should be tons more of them to begin with (4 per sector, seriously??!), and some should come in bigger sizes.
On the contrary, I would think that it would be valuable to respawn asteroids, especially near a homebase. Without respawning, transportation time takes longer and longer and longer, until you finally have to move your base to get anything substantial built.
Limited resources are a fact of life. Think of all those fictional/non-fictional empires that went extinct, or teeter on the brink, because their resources ran out (the Klingon Empire, Krypton... the Vikings, Japan... really you don't want the complete list.) And how exactly do you explain a respawned asteroid? Defies logic at the most basic level.
Of course for an asteroid-belt to be an asteroid-belt it needs A LOT of asteroids, not a measly sprinkling of them (lag inducing, of course...)
If the above as I've described (and I'm surely not the 1st to do so) was implemented, you'd probably die of old age before needing to move your base. But, being forced to move your empire due to lack of resources would certainly make for an interesting (if inconvenient) game dynamic.
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