Add flashlight action icons in 16px, 22px, 24px and 32px.
Looks pretty nice to me! I find myself wanting some little lines coming out of the top of the "on" version though. I guess that means we would need to add them as well for the "off" versions too though, and maybe that would look weird?
Reminds me of these: http://store.t-studious.com/wp-content/uploads/2016/12/Maglite-2D-LED-Torch-.jpg
I like the 32px version, but it kind of just looks like a tube with the 16px flashlight-off icon. What if you turned the head of the flashlight to the right? Then you'd have a bit more space since our HIG allows icons to go past the left and right margins sometimes. The battery icon we use in the Breeze Plasma theme does this. If you put the button on the top, then you might even be able to show the button without the red slash cutting it off.
The only issue with turning it to the right is that having the flashlight upright reflects the way the user would try to use it IRL. Point the phone and press the button.