Maybe some OVA's in the best of chances.
Well... even though ,IF there were new series on the way, I would say the 10 years period (story) between DBZ and GT would be good to be focused.
Other ideas:
That ressurection wish (to allow a comeback) could be well received by the audience, but by me... not that well. I think that formula (Z style) is ran off. Tired. Enough!
If I were in charge of bringing Dragon Ball back, I would possibly continue the story with Goku Jr. and Vegeta Jr.:
a) timeline starting from the DBGT 45 minutes special, and ending on the last DBGT episode: Tenka Ichi Budokai.
b) timeline starting from the last GT episode's Budokai, going on until they grow up....
The series tiltle could perfectly not be Dragon Ball "XPTO" or something like that. In fact it really SHOULDN'T feature the "Dragon Ball" name at all!!
Why? Because it would be supposed to be new!! Not supposed to feature Krillin, Goku, Vegeta or others...
Of course that would imply a diminished comercial success/TV audiences. But who cares? Not me. It would be fresh and that's the idea
Much less fights and powers, bla, bla, bla... you get the idea.
Or...
...the whole story before Son Goku! The story of the Saiya-jin with Bardock as main character!!!
Ending the series with the arrival of Goku on Earth. And the rest everyone knows... 