Eternity labs was one of the best ones I've found in terms of being optimized for simplicity and low filament cost - it also looks quite nice without being hard to print or needing any assembly.

That said, I didn't need stackable bins and wanted to make them as large as possible and with as little filament as possible, so I cut the protrusions off which make them stackable. I also copied the hex pattern to the base to further reduce filament usage.

I didn't change the scale of the model, I just stretched it to end up being 9x11x6.5 and it still came out nice despite the pattern on the sides being a bit distorted. Still plenty sturdy as well with the holes in the bottom. At that size, I got it down to 373g (solid version would be 414g) although it does print about 10% slower since the bottom is pretty much all perimeters.