Amazing read I love what you have done so far. Am I right in assuming the main character is mainly a top? regardless I'm extremely surprised and pleased with the 2 current options making me believe that he is. I don't think there's a single character you've created that I don't like so far I'm excited to see everything you have to offer here.
In the end, I want it to be a case of him being what the player wants him to be. That the current two options are more dominant simply is down to the fact that it makes sense that they would be earlier in the game, with the player actively wanting to be dominant and pushing for it.
But the two current scenes are not needed for the romance of the characters involved and there will be other angles to them with a different tone.