I ended up building a lot of small and specialized designs, on both offense and defense, bombers that rely on staying out of engagement range, torpedo ships that destroy defenders from across the map while escorted by capable strike craft that sort of thing. Easy to add to the fleet and no loss hits too hard.
On the other side I build a bunch of fortified pillboxes with minimal crew and ammo on the same assumption. Just plop more down on a front you know is gonna be intense. Maintenance stays low and it becomes harder to dislodge you.
But that was a while ago. The meta could be really different now.
