Just was checking out some clips on Rebels that may be of interest.

This one shows that there looks to be some cool stuff as far as the Empire is concerned.

Going by this one and this one there will be old and new characters in the series.

And this one popped up in another thread, but looks great.

I am liking what I see so far.

Definitely no Luke as far as the main cast of Rebels are concerned unless it overlaps the events of A New Hope.

Han & Chewie is possible along with Leia, Obi-Wan very unlikely unless its on Tatooine and only the audience realises who he is I'd suspect.

Thrawn would be a nice easter egg though, Admiral Pella I assume is a new character, that might not be Boba Fett since he has his father's helmet so why use a different one?

The Chopper video was nice, expect to discover its the most experienced veteran aboard the Ghost!

Any further word on those toy releases specifically those relating to Star Wars Rebels which i think some of those pictures are based on?

There is nothing to say that Obi Wan stayed on Tatooine the entire time. Toy lines usually release just before something premiers, which can sometimes be a detriment as it may give away some secrets.

You know nothing says they can't have Luke having adventures on Tattooine either...

Still does this mean Leia learns where Obi-Wan is because of this series interacting with him?

The guy who posted the second film you link to admits its a fake on his youtube channel... of course the fourth seems to overlap, so who knows... although, the style of these images are very much in the vein of CW, and from what I've come to understand the style for Rebels is going to be different. Not that it wouldn't be cool to see an older Obi-wan, Han Solo & Chewie and so on.

A Luke and R2 team-up set in this time frame, which I understand is somewhere around 10 years or so (?) after RotS, is kind of difficult...