So I started a collab by accident with Talhydras. I call it the GTVA Khnum. It is made of four ships that can attach to each other: Two GTVC Heqets, the GTVD Anhur and the GTVL Mehit.
The GTVC Heqets can detach from the big ship, the GTVD Anhur, to attach to the fort module, the GTVL Mehit (adding subspace Jump ability to it) or to serve as escorts for either platform. It's basically a battlegroup in one ship.
The Anhur can be deployed with or without the fort module.
With their powers combined you get a Colossus-esque ship made of 4 parts: The GTVA Khnum
And yes, you will be able to make your own attachables if you want.
This baby has gone through a lot