As I looked at the changes, I wasn't happy with how much they are just tearing apart TMS/AMS, and leaving soldiers a lot more vulnerable to damage.
My proposal is this - 50 second up time, 25 second down time.
This makes it active while not completing taking it out of a soldiers toolset for survive. This also allows a soldiers a slight larger window to survive. Make 25 seconds count, or soldiers will have AMS/TMS up agai.