I don't think IS and the Japanese market is well suited for homosexual relationships. I trust them to write in implicit relationships pretty well like Soren and Ike, but doing things explicitly increases the odds that stupid things get written. I'd rather they make the gameplay better than putting in an excessive amount of time writing support dialogue anyhow.
Then there's the cultural barrier around these relationships. Western culture is more willing to address this publicly, so I think we tend to have a slightly better way of writing them over here. Even so, this subject matter gets pretty messy and complex, even before character development comes into play. Hell, check out Dragon Age Inquisition or the other two Dragon Age games if you want some of the less conventional character stories.