Marigolds are great sun loving flowering plants that come in many sizes and don't require a lot of watering... they like it kind of dry. Easy to start from seed as well.
Coral bells (Heuchera) are great and low maintenance for a ground cover idea. Mine get the spring sun, and early morning sun, but then shaded during most of the day. They can be full shade to part sun. Comes in different heights and the low growing ones I have stay green year round, flowering in the spring. Easy to divide too. I just cut off a section and stick it straight in the ground in another part of my garden and it just keeps going! For the low growing, mounding variety I have, I break apart a rooted section grown off the side of the mother plant and just plant that.
