You know who I'd like to see appear on this show? Vincent D'Onofrio.
Much like Giancarlo Esposito (Gideon), he's done great character actor work and has often been the best part of shows or movies he's been in.
He can play good (
Law & Order: Criminal Intent), bad (
The Cell), sympathetic (
Full Metal Jacket), crazy (later on in
Full Metal Jacket), so they could put him in any number of roles/character types. He's been one of my favorites for years and years, and I've often sat through otherwise lousy movies (or movies I really had no genuine interest in, like
The Judge) just because I know he's going to be there, putting on a "here's how to act" clinic.
And he's obviously okay with doing genre work (
Daredevil,
Jurassic World), so a
Star Wars project shouldn't offend any "I'm a serious actor, dammit, and above all this pew-pew-pew foolishness!" sensibilities he might've once harbored.
Good writing/story + good actors to convey it all...and the rest almost takes care of itself.
Because you see what happens when one (or both) of those foundations are missing...
ahem