After the disaster of the last three films they better pull a rabbit out of their hat. The only way I'm interested is if they can sign all the original cast members that are alive. Other than that-sorry Disney but I'll pass.
dozens of planets
hundreds of characters
5000 years of history
The upcoming trilogy is just the tip of the iceberg. But, yes, if they have not signed on already, the film makers are in talks with the actors who portrayed the surviving characters to appear in the upcoming films. But, the appearances are reported to be short in screen time, because the trilogy is more like a passing on of the lightsaber to the next generation. There is also talk of bringing back some of the characters who died during the previous films. Which I think is a bad idea. But we will see what we shall see in 2015.