I think that Ren is the highest bidder at this point, but there's no saying that since she was in love w/ Shou that she can't be again. I think that her turns into competition at some point and she'll come to terms with his previous issues. it'll be an interestingly even battle. if ren doesn't start trying to get her for real, shou might win.
suitability wise...i personally like ren better

she understands him pretty well and as one of the few ppl that do, it'd be a waste for him to just let her go.