Hi Sharon! Somehow I'd missed your thread!
That shed is so cute, and the garden is gorgeous! Something dwarf would be nice on the right where the door opening wouldn't be an issue. There are some cute dwarf Forsythias on the market that could work nicely, and I think some are variegated, which would be nice for all season interest. Blue Mist shrub has a long bloom season in summer, and those typically don't get too big. There are variegated forms of those too.
On the left side, perhaps a flat trellis with a vine would work well, so that the door could open all the way.