Here's a stupid idea: 18" diameter wheels with black lip to simulate 15"!

its all about proportions.

my car has 17" wheels and tires. the fronts are 26" tall and the rears are 28" i hate the rubber band tire look. if you put a decent size tire on the rim they look good. that is my opinion.


This..He's got a clue: it's all about profile..( reference to wheel/ tire profile, in reference to fender lips/ clearance/ what you want "and can afford ".
What do you want it to look like,what performance parameters you want,& what's your time line and budget??