I was looking at the following below at IKEA. They are pretty narrow (3.5"), but I think should hold the guys well. At 45" you can hold a fair amount. I thought of getting 1 for each element (if they fit) + special items. Only downfall is trying to get them all to line up on the wall perfectly. Crooked ledges would drive us crazy.
Level is definitely your friend when mounting items on the wall. I purchased one and have used it repeatedly for mounting tvs, shelves, etc.