I know ludia have said that they are not going to do a water update this year. But maybe my idea is good for in 2023.
My idea was that there is in every 250/500 meter radius a some kind of watertube or even an small submarine place. You can acces this place and than youre entire map changes to water. With water dinos that spawn. Water strike towers. Water raids etc. And you can acces the submarine spot again and go up to the land again.