Here's a thought: add a new mining commodity just for Gallia - Prometheum Ore. Make just 1 medium size field of it, and make it worth $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ in Sirius, especially at different research stations.
Or another I suggested in another thread: Make Uranium Ore a mineable commodity that can be mined in Leeds near LD-14 and have it sell fairly well in Gallia to entice GMS to be there, but ALSO make it sell moderately well in Manchester (their new MOX production facility) to maybe entice BMM to try to sneak mining ships in there also. Also, have it sell well in Rheinland and Kusari.
Reduce redundant mining in different sectors, and instead just make different commodities for those systems. Ex) Get rid of Platinum mining in Nagano and make Alberta the primary source for that. Get rid of different locations for Copper, Silver, AND Cobalt all in Omega-7. Make them solitary fields of each and force IMG/Kruger to fight over them (or at least be sneaky), or put the Copper fields in Nagano instead (unless there's a high Kusari sell point for Copper...can't remember off the top of my head, but I know Denver buys it for a lot, and that's not a bad run).