Maybe a series that takes place within Episodes 4 & 5? There's at least 2-3 years worth of time in between them that could be explored in the OT-era...
"No thanks. That's the one area that's already been mined even more thoroughly than the Clone Wars.

"
Really? You mean in books? Just about every era of Star Wars "history" has been covered to varying degrees in books, comics, etc. INCLUDING the Clone Wars era but the gist of my post is that I want to see some different areas covered in an animated (or otherwise) series.
I know that eventually we're going to be getting a live action series set between Episodes 3 & 4 but I would like to see the continuing adventures of the OT characters that got most of us into the franchise from the start. Don't get me wrong, the PT characters are enjoyable in their own way, particularly since we're now getting half-hour weekly episodes featuring them, and I'm sure the live action series will be interesting in terms of helping fill in some more of the "gaps" in the Star Wars timeline but the producers/writers can't make any fundamental changes in the characters/storyline in either series because the outcome is already known and set in stone based on the movies already produced.
Frankly, I'd just rather see good adaptations of some of the post-ROTJ stories. ROTJ was a nice "cap" to the six-part series but there's so much more story to be told. I've heard that the X-Wing series was pretty good and the Thrawn Trilogy, already widely regarded as Episodes 7-9, if done correctly, would be awesome to watch even if relegated to the small screen.
Of course, whether it's likely to happen or not remains in doubt although I'd bet that if enough people demand it and/or Lucas needs more ways to "milk" the franchise he may yet consider it. Maybe. Who knows? Just posting my thoughts.