I am sorry to say but this is a clear case of where a map isn't great and shaders are doing all the work to make the screenshots look good.
I can't do a full review without a download link but here are somethings that you could improve
- On the second screenshot there is a mountain that has lava flowing down it; the terraforming there is pretty bad, the mountain is really round. You could try smoothing it out a bit.
- Not all the builds are the same quality or the same style, you want your map to look as if it could have been built by one person ie the style is consistent throughout.
- There is way too much water. Water isn't great for pvp so people don't tend to like it that much.
Hope this helps