I agree that the big wheels look out of proportion on a traditional hot rod. I've looked at a few really nice cars that were let down by the wheels. One was a 34 Highboy with a blower. Everything about it was just right except the monster wheels. I think it had 20's in the rear and 18's in the front! They made the car look cartoonish.

Having said that, I will admit that except for racing tires, true high performance tires with modern technology in anything less than 17" are fast disappearing. There are a few in 16", but they are mostly replacements for mid-90's hi-perf factory cars. If you are satisfied with 70's era tire technology, then Bf Goodrich and Cooper have you covered.

I have had to go to 18's on my sport car project. I tried to stay with 17's, but couldn't find any traditional style wheels I liked that would clear the 13" brakes I'm using. Most traditional hot rod wheels (like Torque Thrust's) looked stretched and out of proportion when you go over 17". I've had to go with a more modern wheel design.