I'm generally unqualified to comment on this sort of thing, but since you have had no responses in a month, I'll give it a go.
In your brewing room, I'd add a work table, maybe under or next to the shelving.
In a perfect world, your floor drain would be a trench with a sloped floor. If you already have that in there and can't change it, you're still a step ahead of most since you HAVE a floor drain. So good on you for that. You might want to position your brewery so you can get behind it with a hose to spray things toward the drain.
Finally, in your cold storage, I see you have a bottle conditioning area. If all of that is the same temp, it might be a bit cold for bottle conditioning. You have fridges for hop and yeast storage, but if that cold storage bottle conditioning area is separate, I might use that for hop, yeast, and bottle cold storage and use the warmer storage for conditioning. What about keg cold storage? If you can split your cold storage between fermentation and beer storage, you might be happier in the long run if you have a lot of keg and bottle beer in reserves.
Envious of the space for sure.