I used to have a real mish-mash, but awhile back, I started reading books and articles about how to get your house ready for sale - and one of the tips I came across is to make sure that all of the hangers in each closet are all the same. I ended up tossing all my old hangers and buying a bunch of plain white plastic hangers, making sure they were all the same brand/size. It was amazing what a difference this made to the look of the closet. I did this with all of the closets in the house - it wasn't that all the closets had the same hangers, but that each closet contained hangers that were all matching in colour/size/shape. It was kind of amazing seeing everything all lined up perfectly, and how it created a sense of order and space in all of our closets.
Meanwhile, I still prefer the look and ease of having all the same hangers in each closet.