I also found this mod that adds research to increase the range of laser towers:
I was quite excited with the Artillery Cannon being added with its range research, unfortunately it is specific to the Artillery Cannon. It would be really awesome if we could do this for weapons and turrets too.As you cannot actually modify an entities range this mod creates a new entity for each range level of the turret. A script updates turrets when they are built. Another script updates turrets when research is complete. There can be spike lag when finishing research in very large bases as it checks and updates large amounts of entities. For convenience the turret will revert back to the normal appearing ITEM when it is picked up but will change back to the current level when placed.
Ideally we could create some kind of research variable and then apply that wherever we want, increase Flamethrower's fire count / ammo consumption, add pellets to Shotgun Shells, etc, it would be a lot more flexible and intuitive though I would be happy just for range research so we can at least cover the three basics of any weapon.