I agree with most of what Blogaugis has said, though I do want to point out that resources in Aurora are technically infinite as you can always generate new systems. Rate of gathering of course flatlines as the empire expands to infinity unless the empire is broken up i.e. Sol is abandoned, which most players I think are loathe to do.
There is a... somewhat cinical and game-y question:
Do right now civilian ships cost resources?
Because, I almost see the potential of unlimited resources by salvaging their wrecks.
You allow attacks to happen on civilian shipping - only to extract the resources from the wrecks!
But if this is really a way to get infinite resources... boy, something really feels off.
As for infinite systems...
Well, that limit is probably decided by the capabilities of your computer.
I guess the last resort is spacemaster.
But really, I think that it might be an interesting way to have planets regenerate a very small portion of their resources - as they catch those TN elements thanks to their gravity... Though, it would encourage the player to expand rapidly, like a time limit above their heads, as otherwise NPRs going to take those potential resource producing objects of gravity.
So, on one hand, limited resources do give you infinite time, the question essentially becomes can you successfully siphon the resources off of your opponent, while minimizing yours (battle with salvage).
While unlimited, will essentially force you to go out and get more planets than your opponent or risk being outnumbered. Salvage could still play a role, but it is less significant. Although, the "golden medium" between these 2 is decided by how quickly and in what numbers do these resources regenerate.
A formula could be made out of this, but I want to experiment with Aurora 4X, not with excel spreadsheets...