Sorry if the answers obvious and I'm just forgetting but why isn't Jill one of the options at the end? I mean you've already stayed with her and out of everyone, I'd say she would be most likely to take MC in in a moment of need. Perhaps even over Derek due to the fact that it's his sister that MC is upset with, which is awkward.
I like Sage a lot and want to see where her story goes, but at this moment, do she and the MC have the sort of relationship where he'd go to her when he's upset? They only tend to interact when she wants something (help with Chad, guitar lessons, sex, to feel wanted etc.) Of course this could be a way to show how much she actually cares about MC (either turning him away or being there for him).