This is about the earth invasion before invading the Strogg in Quake 2, so I think the technology makes sense.
Also, it's hard to tell how far away the tank is from the marines. While the game is 3D, the screensho is 2D, so depth perception is a bit off. Judging by the machine gun turret on the top of the tank, I think it looks pretty good
I like the idea of fighting by moonlight... headlights blaring, massive lighting effects from massive firefights in the dark
I hope the sniper class (assumign there is one) has a rail gun