I'm a bit confused....If your list is working, then why ask for help?

I think your list looks fine, it's a little low on draw for my preference...And i'd probably cut a sea for an island (oh and split them up 50/50 snow-covered and normal islands, just in case you need to gift after them.)
Also, i think most fish builds have adapted to inkwell by now, making DSC superior...could be wrong though

I would consider adding a few old man of the sea to your sideboard...thinking 3 sowers, 2 old man, But if 4 sowers is working, then i wouldn't mess with it. Threads of disloyality is also an option, and it's better vs. removal then old man and sower.
/Zeus