Since a ROTS-ANH timeline appears to be the timeframe for the live action series, there´s plenty of room to work out conflicts. Little to nothing has been said about that period, so the writers would have more free reign.

The opening crawl to AHN did say the rebels won their first victory against the evil empire, in which they also obtained the blueprint plans of the Death Star.

It would be interesting to see how they did that and ofcourse tons more. I don't see this as live actio though, I would prefer it animated á la Clone Wars.

Me too, except I really don't care for the Clone Wars animation style.

Whenever I see pictures in the "Art of..." Star Wars books, I always wonder why don't they do THAT as an animated series? I mean that kind of concept painting come to life?

The lead-up to that is of course the joining of several Rebel groups who found out the hard way they couldn´t get anything done on their own. Which is why it was called an "Alliance". Prime story-material for a series.