They rebooted the teen titans show again with a new version called "Teen Titans Go!", which has more of an emphasis on comedy similar to what you'd find in "Regular Show" versus the quirky anime style action comedy that the original teen titans show was all about.
As far as powerpuff girls go, I know there was a tv special with them recently that utilized state of the art cgi animation, but nothing else since. I'm guessing that tv special was more of a pilot for newer episodes to be made in that same style, so if there are anymore new episodes of ppg, then you can bet it'll be done in that same cgi style versus the 2d animated one.
As for Dragon ball Z, that really depends on Toriyama if he wants to even keep working on the manga, or retires. I know it's been recently announced that the new dragon ball z movie, battle of gods, is getting a limited theatrical release in the states. And, there's speculation that a sequel is in the works to it. Apart from that, it's hard to say at this point.
As far as what tv shows would i love to see cartoon network bring back, I honestly don't know. I would say Johnny Bravo, but the problem with his character is that he's like popeye, and mr. magoo, in a lot of ways. They're both one note kind of characters that don't really leave a lot for writers to explore.
I would say that i want more dragon ball z, but the reality is everything after the cell saga kind of sucked. If anything, it was almost like Toriyama and the writers were making stuff up as they went along by that point that it kind of got boring. I wouldn't mind seeing a spin off to dragon ball z (i.e. the adventures of uub being the main character after dragon ball z ends). But apart from that, I just think it's best to let it die with a sense of dignity.
Granted, I've seen the subtitled version of battle of gods, and I loved it because I'm a huge dbz fan, so I'll love any anime film they produce by default. However, as a movie critic, the film was very flawed. Unless you're a dragon ball z fan, then chances are you're not going to know who half those characters are. There's very little if any character development. And let's face it. Apart from the surprise ending, the movie still fell into all the typical cliches that we've seen from dbz before. Heck, even the super saiyan god form was unoriginal as it looks too much like goku using his kaio ken attack in cgi animation.