Plantings are easier to install and change, but you'll want to be sure to put them in the right places so they can quickly play a role.
Trees, shrubs, and ground covers are permanent purchases that increase in size and value and take little maintenance. You can even use many edible plants in place of or along with ornamentals. They present little extra work except for harvesting.
Flowers take care and often require replanting, but they can fill in the gaps until your woody plants gain enough size to stand alone.
You can hire a professional, so that they will give you best suggestion to make your front of house beautiful.