Those larger structures are meant for groups though, not solo players or three friends.
Fortizars and keepstars as such are in a good place.
Even an Astrahus seems OK, and cheap enough although it’s a bit too easily killed.
I’d like a small dockable Upwell structure to be more restrictive than an Astrahus (anchor limit per character, maybe nothing bigger than cruisers can dock) but cheap and more defensible so that solo players and groups of three friends too can have a base.
It doesn’t need to be able to fight back to do so, just an obnoxious amount of hitpoints and little enough reason to kill one could make them survive too.