Yeah, I think that two titles like that should certainly be able to find a place in this turbulent market. I'd have the space-based title starring John as opposed to Guy but that's splitting hairs a little .
Hassle? I'm not sure that publishing Green Lantern comics should be regarded as a hassle. The hassle tends to emanate on fan sites like this where people overthink and obsess over things.
I have to go back to my original point on this. These titles are not a priority for DC right now. Look at how 'The Flash' is currently performing in comparison to the Venditti/Jensen run. It's got a better writer on it and has been important reading to fans that have been swept up in the Rebirth/The Button/Doomsday Clock storyline. Hence it's been a much more successful title. That's how you rejuvenate an underperforming series. You have to make fans care and make it almost compulsory for them pick up every month/couple of weeks.