I only did land with WE. All the spikes and trees were created by hand.
There is a great YouTube tutorial for Spikes by a YouTuber named Grian. I use the technique all the time if I'm in need of some spikes.
You need VoxelSniper, but the outcome is way better than by hand in my opinion (if you fix up a few patches) I believe the command is /B E Line (you'd need to look at Grian's Spike Tutorial on YouTube to know how to use it)
Also, having just 3-4 textures isnt great. I would love to see some dirt or cobblestone mixed in with the islands to give it more of a "frozen ground" look.
I honestly hate when dirt and snow/ice is mixed together. Doesn't work well with me.
ANYWAY. Onto the map.
I do think the middle would if been cooler if there were multiple spikes coming off the island at different angles and rotations. Because the ice spike in the middle does look a bit funny.
I defiantly like the addition of trees, and more blocks to the mixture.
I don't mind the rounded bottom of the islands. I used it on the islands in the SG waiting lobby. The technique can look good when done well.
Once again, I like that you've added some more islands around the middle with the singular chest. But in the future, I think it'd be cool to have some bigger islands in their place, and spread the rest of the islands out so they aren't all too cramped. (Don't worry about doing that to this map, those small islands are fine as they are.
As
Trenly had said, the tops of the islands do seem a bit flat, but atleast you've put some snow layers there to give the floor a big of depth.
This map is pretty good, but I think if you added these suggestions, it would be higher in quality.
*adding some terraforming to the tops of the islands so they aren't completely flat
*And my suggestion about the spikes in the middle coming off at different angles and rotations. (If you have VoxelSniper)
I'll wait to see if you update the map, but for now I am sorry to say, but your map has been declined.