hrmn. Thinking about PS4 because i'm comparably familiar with the characters.
Best possibilities would be Hahn or Kyra. Hahn, being what is essentially a researcher or grad student, would very much be reasonable on the roommate front, though chances are it'd be a permanent arrangement until he marries Saya. Kyra is perhaps a bit impulsive, but otherwise personable and probably would be fine.
Demi would also be good, but I don't know the weight of PS androids and may have to consider the structural tolerance of where I'm living, alongside the fact that being the direct control to Nurvus, while indeed an *important* job, isn't one that pays money, even if i would save on food. Wren has the same problems, only moreso, and...isn't really meant to interact with people much. Also he's more visibly a robot and that'd get looks. And probably the government.
Alys would be pretty good as well (assuming this is pre-game and she's not dead), and she'd easily help pay the bills, but...I get the feeling the sort of work she'd get into would probably invite trouble, or end up with her at her endgame state.
Chaz is a teenager. I guess he'd be fine at end-of-game, but start-of-game Chaz would probably be a pain in the ass. Rune...not sure, but I don't think he'd help too much outside of paying rent, and there's a good chance he'd be a jerk. Gryz is too attached to his little sister and probably wouldn't be happy with the arrangement (also good luck with all the questions), Raja is a pile of hell no (if I wanted an old man to tell me bad jokes 24/7, I have my father for that), and I don't know where to start on the issues that'd likely come with Rika being a housemate.
...but at least none of them are Seth.