This is a very nice showcase you have made! The terrain you made looks outstanding, and the view looks amazing on the islands. The realism of it makes it unique and impressive the nature and detail is spot on. However, I do got a few suggestions.
Adding bushes or plants the more lively parts of your showcase. Of course you wouldn’t want just trees placed on both of the land parts, however things such as shrubs or other variety of trees could add a lot in terms of variety to your build. The open view where there’s nothing in the water is my personal favorite, however like said above mini islands in the water could improve your showcase so it won’t just be the big islands and that’s all I’ll try adding more so you could have the full detail your trying to go for.
I would suggest or recommend adding flowers, bushes, rocks, plants, that could go on the mountains. It would be very amazing to see what it would possibly look like a bridge leading to the other islands could add more detail to it. Maybe you should add quiet music, that’s kinda peaceful and relaxing just a simple suggestion.
Anyways hope you keep improving your showcase that you have made. As well asking for rate my builds is against the forum rules.