Anything more than combat would require some extreme coding to allow the crew to do something that you as the pilot can't.
Besides which, there's plenty of combat for miners. Pirates exist, you know. And for Tradeships. Pirates again. And even if the trade ships don't have need for gunners, you appear to be getting 9 pips, so you can max shields AND engines and keep one in weapons, if your tradeship has three spare seats. Miners will be able to shoot mining lasers longer with more pips. And explorers will be able to take a break and help any of the others out with what they're doing.
Where is the stuff for combat only?