My thoughts on Supernova issues I have had playing the game.
AI Core world building issues and new players:
1 Core world per system (15-36)
Limit leader placement on size 15-36 worlds
Feeder colony size 1-4 should have 1-3 in all stats
Feeder colony size 5-9 should have 2-5 in all stats
Feeder colony size 10-14 should have 3-6 in all stats
Reason: This will help the AI and new players focus on 1 core per system and enough stats from feeder colonies to build up. Right now most the feeder worlds are like 0-2 in most stats and alot of the time zero is rolled.
I think the bazaar needs more thought put into the design. What I see the AI just buys all the resources it needs vs trying to mine them. I also do not see how the AI can build ships completely decked out in all the resource costing modules without mining most of them. Yet I struggle just trying to build improvements and rarely have any left over for ships. I even own most the mining stations and struggle. So if you want us to fight over them cut the AI from the bazaar or limit it in some way other than credits. The AI in games I play have 100k+ credits easy.
Colony special resources should get upgrades like the core ones so they can grow over the game vs always being stuck at 0.1 per turn.
Colony upgrades should be able to spend control points and change out upgrades.
I did see some improvement to the weapon modules. What I feel is the star bases have very limited HPs, armor, self repair, and a lot less defense fighters. I would like to see a tech tree branch for star bases with modules for all the above.
Reason: Starbases are so weak to an attack that 1-2 ships can take one out even with max off/def modules. Or the AI just attacks them every few turns and the base is unable to repair between rounds.
Military Star bases should protect anything in its range. Like colonies add asteroid mining stations.
A button to send to next core world I do not have a trade route with.
Reason: QoL help...
A button to mine the nearest asteroid I do not have a station on
Reason: QoL help...
I think your idea of only being able to siege core worlds is a great idea and will solve a lot of the wack a mole play. When you take a core you take the colonies and mines.
Map Pin system:
I would love a set of map markers to drop pins on the map to areas i want to remember later for growth. I would like a few basic colors. Like I could have a green pin for future worlds, yellow for future star bases, red area i need to send ships, etc...