There are mods that reduces or removes the range limit between fortresses, problem is like "TheDeadlyShoe" states that the AI is not smart enough to Counter or take into account the fortresses so it makes Hard AI rather easy to cheese when currently Hard AI is the only thing capable of offering a challange.
I think the best solution is simply to make Space Stations the equivalent of Fortresses in EU. Basically quadruple or more the stations hit Points and Shields while giving you slight Upgrades to weapon fire rates or some weapon platforms. Space stations should at least:
1. Give the defensive player time to regroup and come to the defense of the planet like it does With forts in EU.
2. Provide a form of small but not insignificant attrition to incoming fleets
3. Make it impossible for a small fleet to capture a well developed planet just like a 3 regiment stack can't conquer a lvl 4 fort in EU.
As for ground combat I hope they can make ground invasions work like Naval Combat in Hoi3. Dynamic and interesting which creates its own mini story as the Battle unfolds. And they already have naval combat in the engine so it's not like they need to create something New. Just New Graphics and sounds as the mechanic is there ready to be used.
Have slave/conscripted armies work like screens, Heavy armor/Assault battallions work like Capital ships, special forces work like submarines and have atmospheric fighters work like naval bombers. Just imagine it *drool*
