I think the white circle to signify your locked target is a really poor choice of color. There are plenty of maps where the floor is covered in snow. This makes it a bit difficult to see who you are targetting when there are multiple opponents around. I would suggest that the target circle be either colored blue or red depending on what team your Locked Target is on.

Also I think there should be an option to make the targeting circle a bit more obvious. A simple animation like the circle being dashed and rotating would go a long way to making the targeting circle much easier to spot.