CMOS Gain, Sensitivity, Signal to Noise

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Had a really useful discussion this week regards my all sky camera and optimum settings for catching meteors. But it left me thinking, and wondering about my understanding of imaging settings.

In reference to the Camera I'm using (ASI224MC CMOS) as you increase the gain from say 150 to 300, the read noise goes down from 1.1 to 0.8, but the full well capacity goes from 3000 to 300.

So the dynamic range of the camera goes down by approx an order of magnitude. My understanding of sensitivity is that it is the minimum signal that can be detected above the noise. So by increasing the gain - my question is - are you increasing or decreasing the sensitivity to low light signals. If you take the example of a meteor, which only lasts for a small fraction of a second, do you want a lower or higher gain? What if you doubled the gain from 150 to 300, and halfed the integration time and stacked the two images - would that help you pick out fainter signals? Same thing for a very faint star which is better?