If you like the texture of the pencil, no need to burnish, or as I do burnish selectively only where you want to darken and smooth out more! There is an art to burnishing just like every aspect of drawing! These leaves are lovely. For example you might want to burnish your shadow to quiet it down but not burnish elsewhere
these various leaves that are so different from each other are really fun to see together in this way! I think you are doing a great job. My one comment would be to make sure your secondary veins get thinner and taper towards the outer edges
Perhaps if you make the veins that are shaped like scalloped forms, that are technically the tertiary veins less important and more subtle it will work better because if you look closely at your leaf there are probably additional veining which helps to keep it all subtle. I do think you did a great job here though!
I would adjust the following:
1. there is a slight diagonal created by the three buds. I would raise one perhaps on the left up a bit. I also don’t like the way the stems just end because it doesn’t allow my eyes to keep flowing. I prefer to extend the stems below the leaves the way you did on the right
I like this idea so far best. I like how you are adding as the plant grows, just keep going and yes wait to add roots at the end. Is this one orchid blooming or are there more than one flower? Can you send some photos too?