I don't mind him at all. I'm not in love/obsessed with a fictional character so hard that I can't appreciate others. He is a little bland but he's new, they seem to be fleshing him out more as a person. It seems like Bruce is teaching him to be a good detective, which I always admire.
Also I think fans are going overboard with the "better than Batman" and taking it much too literal. Imo it's not saying Duke is better than Damian or better than Tim personally or skill wise. It's saying he is striving to be a better type of hero than a Robin, just playing second fiddle to Batman. Kinda like when Dick graduated to Nightwing...maybe it's brash but it's a reflection of a different culture and age.
I back Snyder and after reading multiple interviews, respect his approach to writing and developing new characters.
Oh, and I do love how he still visits his mother, showing her pictures and trying to help her heal, while she demeans him and makes threats...of ALL the Duke stuff, THAT is AWESOME