I'm not an expert, but I think there's pretty much an infinite number of ways to execute space trajectories.
Just looking at it visually it seems Orion is (perhaps?) taking a more roundabout (slower) route, and it's also ending up at the moon in a different orbital configuration than Apollo.
Another factor, I am sure, is cost. The faster you want to get there, the more fuel you need to burn. I'm also going to guess it's not a linear equation, which means the faster you want to get there, the fuel requirements will increase in something like an exponential proportion.
Therefore slower is cheaper, to a point. If you go TOO slow, your astronauts will starve, or you need to bring more food and provisions, which will cancel the cost savings on speed reduction. So somewhere in there is going to be an optimal cost/fuel/food/provision trajectory for each mission.
So, in summary: different mission, different parameters for optimal execution.
Just looking at it visually it seems Orion is (perhaps?) taking a more roundabout (slower) route, and it's also ending up at the moon in a different orbital configuration than Apollo.
Another factor, I am sure, is cost. The faster you want to get there, the more fuel you need to burn. I'm also going to guess it's not a linear equation, which means the faster you want to get there, the fuel requirements will increase in something like an exponential proportion.
Therefore slower is cheaper, to a point. If you go TOO slow, your astronauts will starve, or you need to bring more food and provisions, which will cancel the cost savings on speed reduction. So somewhere in there is going to be an optimal cost/fuel/food/provision trajectory for each mission.
So, in summary: different mission, different parameters for optimal execution.