The large cost of stations need to be rectified while:
1. There is no synergy between the various defensive installations. PD, stations, asteroid bases do not strengthen each other and even defensive fleet starts in front of bases nullifying their chance to create overlapping fire arcs. If there was a good synergy (due to range or other) the cost can be high, they would still be worth it once the various elements are all or largely in place creating fortress worlds
2. Range is short for all defensive installations. Bases have even shorter range then PD even though the later is cheaper
The logical solution to adress the abvoe two poitns is to outfit all PD and bases with either:
1. Small Craft
2. Rockets/torps
Small Crafts are extremely vulnerable at long range though, so this narrows down the valid options to rockets and toprs which can thus be simply countered. Everything else can be picked apart by a player withouth risk
Regarding firing arc: My recommendation was to create a new type of weapon: call it Stationary Heavy or Super Heavy.:
1. Their range should even be higher then heavy variants of equivalent tech (laser, coil etc) and thus an attacking force would be forced to close in as fast as possible as their heavy ships would be in direct range
2. Small ships should not be hit at long range by these to prevent one-shot ship destruction and not to discourage players from taking along small crafts to sieges (like now) when autoplaying the combat
3. Firing arc should be 360 - ideally dedicatged art would be created for hte icons and for the stations yes, but not much and not a must. They can be placed at any part of the station just need to be able to rotate to where the enemy is (just like point defense guns)
4. Allow these guns on PD, starbase, fortress and asteroid base to enable synergy between them. A planet with 2PD and 2 starbase or evne asteroid bases would thus be able to fend of small fleets with a couple of heavy ships and a planet with 3PD and 2 fortress would be a really hard nut to crack worth the investment for the 1-2 most important worlds
5. Putting these into new research would also spice up the research tree and make it a bit less harder to turtle which would be rectified with the defensive power they now provide