Melissa K, could you post a picture of the ramp? I'm certain you can get help when someone sees the situation.
Yes, it would help if you could post a picture, Melissa. And let us know if it will be in sun, shade, etc.
Vines and creepers like natural material over plastic or metal so you might want to make a combination of materials. Make sure you build it tall enough for walking too as well as allowing for foliage. Upright posts of your choice and use lattice work over the top to keep vines from gowing down to be a nusiance. Anything that grows through the openings can be pruned. You can even make it rain proof by making a small slant to one side if you desire. Keep in mind that you can keep it sparce and beautiful at the same time. Overplanting only adds more work.