Haha, I see. I look at lots of people’s instruments, so I don’t always remember who has what.
This is you, then.
In terms of optimizing your sound, there’s a few things one can do. The first is just to practice and refine your technique. Skilled hands can make almost anything sound pleasant 
Beyond that:
Shamisen sound mostly derives from the skinning (past a certain point). If you don’t like the Hakuho sound, you could try out Hibiki. The boom gets to me, but i think I’m in the minority there.
I would always recommend a natural skinning if you can swing it, but I know it’s not possible for a lot of people.
You can also have a shamisen luthier take a look at it to see if there are any issues in its construction that might need to be corrected. Heavy wear to the neck, action misalignment, slight warping or loose joints can all limit the overall potential sound quality. I recently had an instrument replaned, the action reset, and the joints tightened up. The difference is night and day.
Koma and bachi choices are mostly tweaking for comfort and taste. Koma has a much more impactful value for sound, although I find that different shamisen (and different days) prefer different koma.