Hi Caenwyr! That sea sure is lovely! I'm enjoying how this one is coming along.

Can I suggest something. The cast shadows on the buildings are done really well. You have a good eye for that. One thing I would suggest is adding core shadows(dark small shadows) to the buildings, as it is now, they don't really pop very much and the core shadows would make them pop very nicely.
Like for example you are using core shadows for your ocean already and it makes that thing look like it is climbing out of the image, which is awesome.

Btw, your island top right looks like it is floating for some reason. Can't really point out why at the moment.

All, said, good job so far.