I purchased the game and doing the tutorial. The game is a ton of fun so far. It definitely feels like the old west. I finally realized there is no overwatch but i think it is made up for by the replenishment of your Action Points by killing an enemy. You are always outnumbered and need to use strategy to try to go on a killing spree.
When we use an Overwatch in other games it is used to lower enemy numbers. This is the same thing really but from an offensive perspective rather than defensive. It does feel good to have something different. I also think it fits the theme of an Old West shootout.