[Lazy_Perfectionist]

Desert Eye is a surprisingly wet map. If you want to make more water provinces, you might try miniature islands like the 'Forbidden Isle' in that map. They'll give a strategic stepping stone for sailing nations.

Anyways, I've had a really interesting time playing Late Era Atlantis on Desert Eye. You should check out that map/nation if you want some ideas for water provinces, and aquatic/sailing.

If I was making a water heavy version, i'd at the very most triple the number of provinces. I'd probably go for less, but I'd have to fidget with a few playthroughs before I'd settle on something.