Moving the close macro minimum focus distance from the ultra-wide to the 5x for Telemacro would be my wish. It's more practical for real-world usage as you don't need extra lighting, as you aren't right on top of the object.
Make the main lens closer to the traditional 35mm.
I like the 5x not being a periscope lens on your ideas to restore round bokeh. I'd maybe make it 4x though, to bring it closer to 85mm which is more flattering on facial features for portraits.
