First, I would like to say I look forward to this expansion.
Second, I hope the Rikti forces dropping in the newbie zones (Mercy Island/ Galaxy City (which sees very few high level characters)) will have the Rikti level appropriate otherwise there will be a slaughter of new characters as they try to get to their missions.
Third, I hope that it might also contain a couple of new archtypes for the Villians that match to the Peacekeepers and Warshades (ie. open up for level 50 characters)
Fourth, this would be a great time for the Council to make a killing selling their Quantum Cannons (temp power) to the various heroes and villians going up against the Rikti.