I always suggest that you match the rim width to the tire width. So, a 5.5-inch wide wheel is what came with the Cruiser, and it is what came with my 2wd Datsun 'minitruck.' A wider rim means a taller, wider tire has the correct contact patch pattern. Tires are sold with specs for rim-width. It helps with traction, steering, braking, etc. A race car employs a spoiler, because it imparts weight on the tires, without contributing to its mass, thus maintaining traction. The additional width and diameter, plus load-rating, means bigger tires need more weight, to maintain a similar traction as their stock counterpart. I doubt anyone would notice it unless they are pushing it hard, like a lifted, bigger tire/stock rim Cruiser on rain, doing cones on a track, etc. Folks doing lifts and bigger tires with IFS may not notice it as much, as double wishbone suspension performs camber changes as the suspension flexes - our shopping-cart-like live-beam-axles respond negativley to suspension compression.
I'm happy running the stock rims, suspension, and 215/75/R15 street treads.