For a nice, sweet scent and a low-lying filler:
alyssum. It comes from pure white to lavender, rosy, to purple. Often will reseed and start up on its own the next year (in Zone 7 anyway.) Very easy to save the seeds on your own for next year. Bees love them.
Lobelia- either trailing in long, colorful tendrils from a mixed hanging basket or standing upright in the front of the garden bed or container. Haven't grown these for a while, but they used to come in light blue, rose, shocking blue and purple.
Yes to impatiens for a shady area- so bright and cheerful. And they spread to cover bare ground pretty easily. Easy to grow too.
Snapdragons are just the best aren't they? I forget they are a very cool weather starter (started out here in February when I'm still hibernating from gardening.
) Either the short or taller ones are all equally enchanting. Don't miss the chance to squeeze the blooms from side to side and have them open their jaws to 'talk' to a toddler or preschooler. They completely believe the flower is opening it's mouth talking to them. Magic.
