I plan on making big updates on Cryo

Maybe you could extend it a bit and make the abyss harder to get into eg: In the mountains.

We could also have purchasable boats and for that we'd need a lake so, we could add a stream or water layer so we could fight off land too.

For instance, maybe we could extend part of the base to go underwater, like not a really steep ramp but, an average one. I'm thinking that this could add a few "supportive bars" C-framed into the ramp for more detail. Maybe a few windows too in the style of the ones at the old underwater base but modernized

On the land we could have a path going up through the mountains and it could possibly lead to where the raiders base would be positioned and where the temporary one is, we could add the middle of this "Lake" I was talking about previously.

The abyss could lead to this underwater extension, where they will have to complete another "Obby" to get through the Hatch, the Hatch could be the same pattern that the floor is decorated with.

The abyss could be first made from ice, then blending in to some rusty metal type material as you get nearer to the Hatch and other "Obby"

We could possibly add a statue of SONICTHEHEDGEHOGXX in the middle of the outpost, maybe for decoration we could put a few Ice crystals rising up before him, though to make this look effective, we'll have to make the statue's arms rise, this would show our leader's true power and that we are not one to mess with.