It would be cool if it was made. Give carriers and frigates a lot more importance due to the projection of force carriers offer plus the response speed of frigates.

But, if you want a game like this, you can check out Hegemonia: Legions of Iron. It is another RT4X like Sins, however it is nothing like Sins. It has Homeworld 2 style unit control, colonization of multiple planets (and often their moons) per system, and a traditional 4X planetary infrastructure and research system where you can choose what specific infrastructure to build on what planets, such as planetary defense guns, living quarters, shields, etc., etc., etc. And wormholes are your only means of travel between systems, and you have to use a scroll bar at the top to move the camera to different systems.

Downsides: Very, very limited unit cap. Try 6 combat ships, 3 spy ships, and 3 civilian ships/defense platforms. Really. This game is not for those wanting epic fleet battles. It is often 6v6 of the best ships on each side standing still and shooting at each other. A lot less fun than Sins by a long shot. Plus the game is fairly old so the effects are not spectacular. Music is great though, puts you in the mood. The mod "Distant Stars" for Sins uses Hegemonia music for its battle music, and it is quite enjoyable to listen to.