I just fought gibor and currently have no active quest apart from the home base marker. is that meant to happen?

Hey! Yes.

Beating Gibor awards you with the mines that you can use to open the gate right above where you fought Gibor. Once you pass through that gate, the next quest will start.

ohhhhhh. you should probably tell people that XD

another thing I noticed: the game seems to speed up if you get into fights.

Oh wow, I didn't see a notification for this..

I added another hint in 1.0.3 for the mines.

Regarding the speed up, that's the first time I hear that and I have never noticed that.. Is your framerate constant? The vehicles move with physics, so maybe something freaked out on your end there.