The simple addition of an Overwatch rule in Flying Lead was a significant improvement to Songs. It was a step further along the path of a free wheeling skirmish game that the core activation method promotes.
However it is restrictive, and restrictions to player behaviour I generally consider to be a bad thing.
The main problem is that the player must place a token showing the area he is guarding. This necessitates direction. It implies facing. There are no facing rules. Every model has 360 degree vision and facing at all times, otherwise flank and rear attacks would be allowed. So why do we have have facing once we go into Overwatch? No reason, of course, other than a desire to not unbalance the game, I suspect.
Once I sacrifice a model’s turn by putting him into Overwatch and suddenly give him tunnel vision to a limited zone, all I do is make my opponent avoid that area. This is intensely frustrating to have thrown away two Actions for no result. I tried to make the case, and build the on-table situation, where I could channel the enemy into killing zones with declared Overwatch ‘dead’ zones. But I could not take advantage of these killing zones unless the enemy was kind enough to stop in the middle of it when I had initiative.
Instead, when we go into Overwatch, we still pay the same 2 Actions but instead of placing a marker token in some distant zone, we place it by the figure. He has reserved an Action. When an enemy comes into his field of vision, which is 360 degrees to the edge of the board, remember, he can shoot. Simple.
Exact same result as Overwatch, with fewer restrictions, that does not break any existing rule. It only unbalances the game if Overwatch unbalances the game.
Moreover, just to go the extra step, the model is not limited to shooting. He can, for example, push the plunger to detonate the dynamite under the bridge when the enemy is actuially on it. In fact he can do any 1 Action activity. And why not? Pull a trigger, pull a lever – what’s the difference?