Hanging pots with annual colour are great.
For patios, you want to invest in some nice pots, so that they are part of the feature and get some nice tall ones.
Ornamental grasses are great for patios, because they have colour year round with their foliage and you can get some stunning tall features
Elfin Flax I have some of this and its soooo hardy.
Succulents are also very good, hardy and you can get so many different types. You can get some great feature plants....especially
String of pearls.
Of course, cacti!!!! They are fantastic.
I like quirky handmade things stuck in pots with the plants too.