I certainly like Fringetree, Chionanthus virginicus, mature size is stated at 20 feet. Mine is in full sun.

Esh, thanks for the good suggestion. It turns out that I had a fringe tree in another bed in front but moved it to the back 2 years ago as part of everchanging design. It is in full sun and doing great.
I think I want something bolder either in color or shape for that area since it competes with KO roses, gardenias,a big holly and pittosporum.

i like vitex or chaste tree. it is not native but i have not heard of it having invasive traits. they seem to stand out in the garden because of their bloom time. there are white and purple flowered forms but i prefer the purple.
also, 'omurayama' japanese maple is a unique tree in that it is pendulous at maturity rather than weeping. slower growing than a vitex but also has attractive form and fall color. mine is just begining to show the pendulous form at about 5' tall.

Here is a link that might be useful: vitex

Catalpa bignonioides is one that can be used as a pollard style tree for a more dramatic front yard sort of thing. It's a bit different and has beautiful foliage, flowers. See Catalpa bignonioides. It may be difficult to find but Nearly Natives in Fayetville might have it.

I just started growing vitex this year. I've come to really like it.

Jeff and Laylaa, thanks for the great suggestions. I had forgotten about vitex as a small tree. That is the leading candidate now. Catalpa may be a little large and may have some pest/disease issues. Maybe for side or back yard. It is avaiable at Scottsdale Farms (no bargains but good variety)as are vitex.