SALVAGE RIG! YAY!
My gut reaction is this seems small, seeing as you're burning supplies dragging it out there, and additional supplies to deploy it, and you're likely needing escorts to keep it safe.
Yeah, I'm not sure this will stay in actually. It has some other problems - it's either always worth it to deploy the rig, or always not, depending on the battle size.
I love the idea of this mechanic! I hope it will stay in, pending whatever adjustments to the numbers are needed to make it worthwhile for people willing to lug around a rig in their fleet. It's really cool because it adds a meta-objective to combat for the player: deploy/defend your salvage rig. (and for the AI, to destroy it.) Just for veracity pirate fleets should also sometimes deploy a rig in combat.
Combat needs more stuff like this that the player and AI can both deploy for advantage. It gives both teams something to hunt and something to defend, which overall adds much more options to the way combat can play out.
Here are some more things like that:
-Sensor ship that provide sensor radius increase to all friendlies on the map while deployed.
-Scout ships that improve speed/maneuverability and nebular navigation to all friendlies on combat map (and buffs in campaign map)
-Telemetry spotter ships that provide buffs to missile accuracy and gunfire accuracy/damage to all friendly ships within a certain distance of telemetry ship. (so you'd assign these ships to escort heavy hitters a lot)
-Troop ship that increase chance of successful boarding if deployed to battle. (you didn't deploy the troop ship? Then you can't use it in the post battle boarding dialogue. Don't remember current status of boarding dialogue)
-Medical ships that reduce crew fatalities in/after combat while deployed (if crew even still exist in the game)
-Command and Control ships that increase command points and speed at which friendly ships respond to new orders and do something good to CR. (every capital ship would have this, think of those pits full of guys with computers in star destroyers)
Notice a pattern? It's all replacing stuff that is currently combat map objectives, which don't make sense and aren't particularly fun, or XP skills, which are unbalanced and just reward hours played by the player character, rather than real skill building by the actual player. Basically I think skills are totally wrong for this kind of game. Growth and improved capabilities should come through learning to play the game better, coming up with better strategies, and getting/deploying new and better ships. Not "XP skills" which are points for grinding that magically let you "upgrade your X by Y%" They make sense in a table top RPG, but not in a game that uses the arrow keys.
*Note since officers aren't actual humans who can grow better at the game, there might be more potential for the XP and skills for the officer characters rather than the human player character.