It sounds like you may want to have some kind of grid layout to better keep track of positioning and movement. They have a turn based strategy game in the example projects that you could use as reference. The ambush thing is fine but you still need to determine the location when you check for ambushes to make sure it only ambushes nearby targets. With a grid you can pre determine every possible actions, movements, locations before the turn is played. I guess it depends on the complexity of what you want to do but from what I’ve gathered so far, using pre-determined world positions within a grid or hexagon layout would be better. And then it would be easy to implement features like certain terrain tiles cost more movement points and what not. But I’m still kinda just guessing at what you are attempting to do. Good luck!
I was trying Wasteland 2 the other day, kinda sounds like what you are trying to do!