Polymaker Light Weight PLA Filament Grey 0.8kg, PolyLite 3D Printer PLA Filament Grey Low Density, Print with Most 3D Printers

The most engineering-minded consumer brand in this space. Polylite is their everyday PLA, PolyMax adds impact resistance, and PolyWood nails the timber look. They publish data sheets and actually explain what's in their formulations.