I propose that Ashton Kutcher should play Waru, who has returned from his other dimension and can now take a humanoid form, making him look like a dude covered with raw meat (or Lady Gaga).
Kutcher is the only actor awesome enough to play this super-duper awesome character from the greatest Star Wars book ever (up until Legacy of the Force was even awesomer).
And Seth Rogen can be Cade Skywalker because they are both super awesome, too!!!! Oooooh, and Nicki Minaj can do a remix of John Williams' theme!!!!!!1!!!!