The car was designed and engineered for 15 or 16 inch wheels.
The 17s I bought look great but ride rough, so I made a mistake.
If you want bigger wheels and dont mind spending huge on tires and risking bent wheels and a really rough ride on city streets, 18s look fine to me, 19s look too big to me and 20s look absurdly large to just about everyone.
Its your ride ... I would also love to see pictures of one with that low milage. I got my Legend 4 years ago, with 55,000 miles so you have found a great ride. Enjoy it.