In no specific order.
1. A reboot. I cringe at the very possibility that Disney won't know how to do a movie that would fit in the Expanded Universe and decide then to create a alternate canon.
2. A movie that invalidates and/or contradicts events in the the Expanded Universe. Let's say a Sith cult rises in 9 ABY and threatens the entire galaxy, but wait that is the period where the Thrawn Crisis took place. Yeah, that never happened, we are retconning this so that the live-action movie can be right.
3. No asspulls. Don't use the Force as the only explanation for everything that happens.
4. Fanservice in the sense of of bringing elements from the previous movies for no purpose. If you intend to bring back beloved and iconic characters at least make them relevant.
5. Something too kid-friendly or catered to teenagers. Remember its Disney we are talking about.
Also BONUS (for teh lulz)