I don't know if this helps or not, but in the early spring my trees are bear and there is plenty of sun for Daffodils and Tulips and when they begin to fade the Hostas come up and cover them. I also like the monkey grass ( Liriope muscari) and a few Helleborus.
I love your driveway, the stones are great and would really look awesome with some Hostas dotted around. Also they got those dwarf tulips and Iris. I wonder if they would do good there?
I can tell you a few good drought resistant Hostas if you cannot get a hose out there, like Grand Tiara and Golden Tiara.
