Shane, the Ford Barn's Model A forum has a strong bent towards pure restoration. A good number of us here are not restoration guys, but still love our four cylinder Model A's, and we like to make alterations (improvements) to Henry's original design. This forum is still a great source of information about most aspects of Model A ownership. Discussion of alterations are often, but not always tolerated, so we take our chances every time we bring them up.
I like to run 15" tires on my Model A's, either wire spoke or steel centers. My visual taste is toward bias ply, but I have radials on one A and it rides pretty nice. Of course, do what you want, but you might want to hesitate posting photos of modified cars that will upset the purists.
I grew up when most all running Model A's had sealed beam headlight and 16" wire spoke wheels, so that is how Model A's look best to me. It was a rare Model A that had been "restored" with 21" wheels and original style headlights.