What Atrocities asks for sounds like Battlecruiser and its sequels, not that I would recommend them.
But seriously, depending on how SEV is set up, I don't think what I'm suggesting would take a tremendous amount of work. If in SEV all star systems already exist like they do in Starfury (i.e. 3D objects laid on a 2D grid), then binding SEV and Starfury together would be a lot of work, but not an impossible amount of work I think.
Right now in Starfury everything is so boring and static, when in SEIV, lots of things are happening, i.e. new ships amd bases are being built, big battles are fought, planets are conquered or glassed, the population and infrastructure of planets change over time, research is conducted to enable construction of bigger, more powerful ships etc., which makes it alive and interesting.
In Starfury, the ships that populate a star system are fixed when you enter it. Freighters tell you all the time "On our way out of the system" but they never leave. If pirate ships are in the area, they fly about until they meet Terran ships who kill them, and then no more pirate ships show up unless you leave the system and re-enter. But in SEIV (and presumably SEV), even AI-controlled ships move about with a purpose, not just existing to add targets and scenery to the Starfury player.
Some planets are called industrial centres, farming worlds, military bases, research centres etc., but none of that matters except as places to repair, buy stuff and get missions. But in SEIV, if you destroy an AI controlled research centre, it gets less research points. Destroy an orbital space yard and its starship production capability is hurt.
In Starfury, the galactic news is canned, scripted stuff. In a dynamic SE universe, the news could be totally dynamic, i.e. a big battle happened between the x empire and the y empire, the x empire has destroyed a large planet of the y empire and the citizens of y empire are enraged about it, x empire has signed a Trade and Research agreement with the y empire, rumors have it that x empire has assembled a large war fleet equipped with powerful new weapons etc. Exploring such a universe, watching the ships move about on their appointed, real, tasks, would be splendidly fun!
Another way to expand upon Starfury would be to learn a few lessons from the Grand Theft Auto series. Let the player buy properties. Buy a hangar and you can park a starship there while you fly about in another one. Buy a freight company and you can have computer controlled freighters transporting stuff and earning you a profit, though you need to come to their rescue if they come under pirate attack. Buy a whole starbase in a crossroads system and you get to equip it as you like and it earns you a nice regular income from being a trade centre. And you can come running back to it for fire support if you get chased by a big, powerful fleet.
