Great topic! Should generate a lot of helpful information for everyone.
I identify vascular plants. For flowering plants, I often find observations with only close-ups of flowers from the top – the pretty shots. Sometimes this is enough, but more often I need side views of the flowers, stems, leaves, and whole plant too.
For trees, conversely, I often see just shots of the whole tree, without any close-ups of leaves, bark, reproductive structures, etc. If it’s a pine tree or other conifer, look for cones on the ground under the tree (or still attached is even better) and capture those too. (For that matter, the contents of the litter under any tree can be very informative.)
For ferns, add close-ups of both top and bottom surfaces of the leaf.
And of course, for any organism, sharp detail can be important. Getting to know the nuances of the camera’s autofocus or manual focus is worth the effort.
Also, when details are missing, sometimes a good accurate location can help rule out related species.