This is what works for me,
dwarf day lillies, I also have bigger ones, but my garden is big,
portulaca, i know i didn't spell that right,
ice plant
lirobe (i mispelled that too)
creeping jenny
any kind of dwarf iris, i have african iris, but don't know if it's hardy where you live, blooms all summer.
Do you want only succulents?
I mix them and they grow fine together.
Try small ornamental grasses too, they live fine on my hill with the sedums and hold the soil.
Mondo grass, the spike thing, it also comes in red, don't know the name of it, but they are sold everywhere for pots, i planted it and it came back this year,
I also planted fiber optic grass. Looks real nice with sedum.(may not live this winter, but looks nice now).
GOod luck with your hill.

Thanks, you gave me some good ideas!