Are there ways to get out of panic once it's happened to a unit? Based on the triggers above, it seems like panicked units will be in a downward spiral of continuous panic.
Also, I'm really not a fan of mechanics like "morale decreasing each turn".
You can use tranquilizers on units to bring their morale up, and while they are tranquilized, their morale gets frozen for a few turns; leveling up willpower will also increase the morale pool size.
I understand the concern with morale decreasing with each turn, but it will not turn the game into a run-against-the-clock thing, something I myself hate with a passion, and the very reason why I didn't play X-COM 2. It's there so players don't snail-pace throughout whole missions playing defensively and nothing else but defensively, a known problem for tactics games, and it also makes units feel the passing of time with stress weighing in. You will have plenty of room to play defensively and you will have other mechanics that entice you to play offensively as well, like using energy shields and cover behind your large and tough droids.
I need to point out that morale loss due to turn elapsing will go as low as taking units to an anxious state. While it won't make units afraid and panic on its own, it will make it easier for that to happen.
People often enjoy realism in tactical war games but when it comes to morale mechanics, they tend to overlook it, even though it is one major key aspect of warfare.