I have set up similar scenarios myself to sandbox stuff. I set up a series of terrain objectives as phase lines for the red side. The objectives get more points as the red team moves forward. I used a combination of occupy and touch depending on the type of objective. If I know a Blue strongpoint, I use occupy or destroy. Just use the phase line concept and scenario length as a way to force the time issue. It forces blue to make decisions around troop condition, holding terrain, and time. I know it sounds obvious, but scenario length is critical in this concept. Red has to decide on how many casualties its will trade as the point haul accelerates as they get closer to the exit.
Again, the key concept here is balancing the phase line point acceleration against scenario length. Don't just give a lot of points for key terrain. They have to be given in the framework of making the red team keep pushing against the clock and distance. And forcing blue to always be evaluating if stalling red at a phase line is worth the losses. One concept that I played with was an objective that is literally a single line across the map. As red touches the objective, they get points. Use multiple lines and even a few terrain objectives that blue has to occupy for points can work.
CM's objectives are relatively easy to use, but somewhat limited over scripting. But a little thinking on how a commander would approach both sides lets you use CM unit and terrain objectives to the fullest.