My first set of suggestions since Version 0.4 went live:
1) "Space Mines", "Gives: Gives 5 Combat -1 per turn when played."
This is useful over the span of 5 turns for a total of 15 Combat, which is an average of 3 Combat per turn when played. Tier 2 buildings that do NOT require a strategic resource give a guaranteed 3 points per turn when played and don't need to be refreshed. This makes Space Mines underpowered compared to the Tier 2 baseline.
I suggest one of the following:
A) "Gives 9 Combat -1 per turn when played" <-- Average of 5 Combat per turn.
B) "Gives 5 Combat." <-- This brings Space Mines up to the power level of Modular Farms and Orbital Telescopes, which also require Strategic Resources.
C) "Gives 1 Combat +1 Combat per other Space Mine played this turn." <-- I think you had this right the first time in your earlier game, "Planet Crafter". Just borrow that mechanic. (As an aside, "Planet Crafter" has had a couple of unfixed bugs for the past few years.)
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2) "Arcology", "Gives: Gives 3 Random Points to all active crises when played."
This is comparable to the Tier 2 building "Crisis Response Center" (if I remember the name correctly; I don't have the building in front of me right now) which requires a Water strategic resource to build. "Arcology" is supposed to be a Wonder; increase the build cost to 12 and have it give 8 Random Points to all active crises when played. (This might need further adjustment once Tier 3 buildings are introduced, but until then, this suggestion should suffice.)
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3) The animation for shooting enemies with the laser is a bit slow, especially if I'm shooting the Mothership 20 times all at once. I suggest cutting the animation time per shot in half.
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4) Regarding this selection (and similar selections): make the box bigger and put the planet inside the box. As it is now, the colored outline draws the player's eyes to the contents of the box, making it less likely that the player will look outside that box.