Turns out that you can in fact be clever about combat if you're willing to micro a bit.
Tensions between me and a race of democratic crusader slug people have been building for decades, and it finally erupted into a shooting war. Thankfully my military had been building up, and a fleet of 21 top-of-the-line corvettes jumped into the slug systems in order to made a nuisance of itself. It destroyed numerous mining and research stations before obliterating a star port without losing a single ship, leaving the colony below vulnerable to bombardment.
Meanwhile, on the opposite end of the slug empire, my defense fleet lay in wait with all sensors active. It was a mere 5 corvettes strong, all I could manage before hostilities erupted. And lo and behold, the slug's main war fleet went zooming by on a direct course for my home world. I literally could not afford to lose the star port there, as it was my primary warship construction yard and its loss would cripple my ability to replace destroyed ships. Hyperdrive got my defense fleet to the home system not long after the slug fleet, but the power disparity meant that engaging in open space would be suicidal.
So instead, I waited. I waited until the slug fleet committed itself against my star port (which was putting up a rather impressive fight, but could not hold out for long) and then sent my torpedo-armed defenders charging in from behind. The slugs decided to concentrate on my mobile forces, but being stuck within range of the star port they continued to get battered by it. And yet it still almost wasn't enough. I lost three corvettes before hitting the emergency retreat button, and the remaining slugs turned back to continue the duel against the star port.
And that's when the nearby mining station got involved. It began launching its pitiful missiles, and the slugs turned to destroy it instead. They ignored the far more dangerous and valuable target to destroy a completely replaceable EC mining station. Which they managed, no surprise there, but it took time for them to do that. Long enough for more of their ships to get damaged or destroyed. Long enough for the surviving defense fleet, battered and bloody but with shields recharged for Round Two, to return and end the battle once and for all.
Just a few days later, a second (much smaller) slug fleet arrived. It didn't stay very long.