Here are some game reticles that I've made. The designs are simple and to the point where the player can have something enjoyable to look at all the time white still having some uniqueness when playing.
Border Indicators/Currently Selected
Here are some variations of borders for a sample image that could be used to highlight the shape or used to show that is some sort of item the player has selected. These variations could be animated to give them more emphasis as well.
Here are some simple and generic icons that have a small twist with a slightly rounded edges in places to make them look softer.