I am very against the comsetics, just because of the cost of the base game.
That being said, if the cosmetics were way cheaper (max $5 for a full set), I might consider some of them. There is at least one for the Barb that I like, but due to how zoomed out the game is, it really doesn't ever make sense to buy cosmetics at any price.
They aren't going after the average player for the cosmetics, they are going for whales and people with no impulse control.