With the type of economy that Zero-K has, storage is more like a buffer.
There's not much reason to "save money" for a large project.
Actual good usage of storage exists, such as grabbing reclaim before you can use it.
Obviously, if your com dies you need storage.
But that kinda speaks against storage, since non-decisions don't really enhance the game.
If you want to remove storage(the unit) from the game:
Make energy storage intrinsic to player
Give (tiny) metal-only storage to all constructors
Now your allies will spam constructors instead of storages
If you kinda wanna keep storage(the unit), and want more communism:
Make energy and metal storage intrinsic to player
Rename storage to Metal Storage or Metal Buffer, it doesn't give storage though.
Storage only collects team-wide excess metal (ie, not much in most lobpot games)
Storage distributes stored metal to team as if it was a mex.
If you think storage is 100% useless:
Make energy and metal storage intrinsic to player
Excess metal visualized by idle cons smoking a lead pipe