Make It Feel Larger - Introduce some vines growing on a wall, it draws the eye up and makes the space feel larger.
Cut Down Noise - Add a natural wall, a fountain or even an outdoor speaker to drown out unwanted noises.
Plants in the Shade - If your patio is shady, add plants that love the shade.
Add More Shade - If you patio lacks shade add a sail shade or if you have a pergola, add some vines that will cover it and add some needed moisture and shade to the space.
Add Some Separation - If neighbors are too close, add a small privacy fence, or some lattice and plants.
Fake a View - If you don't have much of a view, add a mirror to make any living space feel larger or add a fountain, pretty sculptures or anything else you would like to look at.
Take Care of Bugs - An outdoor fan will help blow away unwanted bugs as well as adding something that attracts birds and bats will help diminish the bug population.