I would like to see Ores being completly removed followed by a huge set up rework of the standard commodities. (This or Ores being seperated into different "profit" classes).
Also would love to see a proper GB balancing, the new shields were a nice addition, while other changes ruined GBs in a way. (Bring back the normal GB missiles pls, Titan's were a nice idea but they.. well.. bluntly said suck pretty much.)
Story wise? Well, I guess I would re-write the entire lore without Gallia but a re-appearance of the Sol Coalition (I still hate the fact Disco takes the extended unofficial destruction of Sol as canon) or simply make attempts to create less huge wars but more smaller short conflicts with visible but minor impact.