You might consider putting taller flowers at the downhill parts and short ones near the doorway. One foot of space is not a lot so you will need flowers that don't take up lots of space. You can also put a simple trellis or tuteur to grow a flowering vine like clematis or morning glory or honeysuckle where the tall plants are needed. Be aware the wild honeysuckle will be rampant but there are ornamental kinds that behave. Also morning glory can become very unruly. You might also find a smallish shrub, I am thinking pencil holly, for the tall parts. If you can give your location and zone and which way the house faces (north, south, etc) you might get more helpful info.