I don’t mind the open world idea nor the binding on pick up BiS gear, I can even learn to love the art work. What I don't like is the mechanics of the characters, which is D3; nor the art work of the items, which is D3; nor the affix system of the gear, which is D3; nor the lack of skills available in the heat of battle, which is D3.
I’d really like to see Blizzard move away from these things I’ve highlighted and focus on evolving the D2 style of item art, the D2 gear affix system such as described here, and D2 combat mechanics. Also, return the character equipped gear screen to D2 LoD’s style, the picture of a character class with boxes around it isn’t appealing and a waste of space. Also include the addition of weapon switching for all character classes.