Seed magazines should say what's in them: Not just "potato seeds", but what "quality level" of potato seeds.
While evolving crops, I frequently found myself in a situation where I had kept a few seeds of generation X just in case my harvest failed for some unexpected reason, which I intended to dispose of as soon as I had created seeds of generation X+1. In such a situation I would have loved to more easily keep track of which seed magazine holds which generation of crops.
Properly "labeling" the seed magazines would also make it more intuitive why seed magazines sometimes stack and sometimes don't.