Honestly why bother getting the rights to Prisoner of War for Homeland, a series that probably owes as much to 24 if not more? An adaption of a specific space opera property sounds a little safer than a brand new space opera venture.
"A series that's like 24" would be a great pitch for any network; there's nothing like it on broadcast now, and there really should be. There's a big audience there that's not being served. Most people don't get Showtime. Not that a premium cable version of 24 isn't also a good idea...and sure enough, Homeland has been a success. But that same idea on broadcast, tamed down of course, could also be a ratings winner.
Space opera is not a safe bet. A known brand is safer than unknown, of course, but known in America is safer than unknown in America. My first choice for a space opera brand to reboot is Stargate. I've never been particularly happy with what they did with it, but it has a still well known movie and three series of varying degrees of success for its bona fides.