It really depends on the tire, I've had 205 tires wider then 225's of another make, General makes tires wider, falken seems to make tires skinnier. A 225 on a 7 inch is not bowed in, it sits with the sidewall vertical on bridgestones, and kumho's might have a bit of a bulge, but I almost attribute that to just a softer tire. Hard for me to imagine pulling one side an entire inch further out. Or that same tire two inches. I guess it also depends on the rim.
You have to determine your purpose for the car. If you want it to look good then your tire choice is going to depend on what aesthetic you are going for. If you want the car to perform then it is pretty much about getting the most tire with the desired compound, probably less sidewall, unless you are targeting a certain weight then it would be about the tire compound. The cross section seems to be a 225/50/15 for looks/performance/street. Still a bit of side wall so you get cushioning, low enough sidewall so it doesn't appear tall, good width for stock bodied cars. If you want width you can step up to a wider taller tire, just trying to stay in the 23-25 inch range would be advantageous not to make the car look too far from what it was designed around. Up to you how you play around with the width, you will find that some sizes are popular and have more choices because they came like that on certain cars etc just fish around.