I really like what they're doing with Donatello. In the old cartoon and movies, he and Mikey felt more like supporting characters to Leonardo and Raphael, who seemed to monopolize a lot of the tension and character development. This dynamic between Don and Raph in the new cartoon is very interesting to me. I've never imagined Raphael as a bully exactly, but it makes sense. His mean-spirited ribbing of Donatello is certainly believable in context of their personalities. And I enjoy the idea of making Donatello a little arrogant. I'm glad he's finally sticking up for himself and his interests instead of just absorbing or ignoring any teasing. I feel like I'm getting some kind of closure after all these years.
It's weird to be old enough to recognize actor cameos in kids' shows. Lewis Black is very prominent in the third episode, and my reaction reminded me of the time I was watching the Sonic Saturday morning cartoon with my Mom and she had an outbust of, "Uncle Chuck is William Windom!!" It's also weird to see a cartoon character filming something with a smartphone... although I suppose the Turtlecoms were pretty much smartphones themselves, now that I think of it.
I wish April were still a reporter and not a teenager, but I'm going with it. We'll see how it works out.
The Black Nerd did a nice review of the series here. It starts in earnest at about 0:56.