If the roof in the sunroom is also flat on the exterior part of the roof then perhaps put triangular windows in the top part of the wall that would look straight outside and then keep the sunroom ceiling flat. You wont notice its different as the window to the outside will be the feature of that wall.

For a "couple of days a year" get a pedestal fan straight on everyone and leave the features in the ceiling. Seriously...I have 12 ceiling fans in my house and two wall mounted fans...the wall mounted fans are so much more effective then ceiling (and I don't know where you live, but did you know fans have a "summer" and "winter" setting??). Most people don't. Tip: turn the fan off before changing the setting.

To assist with harnessing the sea breeze suggest a beautiful long narrow feature window that follows either side of the pitch of the roof (which will let in a lovely sky view plus breeze), or just have the top triangle as a window. Understand the desire to have the small window there however in a room with big glass/window features, the small window looks like an after thought and is at the wrong scale.

Yes definitely would!! It brings its own personality to the room, allowing you to become extra creative. I love the idea of having a roof window, bringing natural light which opens up a room for sure.