^^^ No worries, mate. You're not thread jacking and I'm always up for helping other Mazda owners out. Especailly the 22v's! Your car looks good, btw.
I simply advise rolling your rear fenders with a fender roller. I "rolled" mine last summer with a baseball bat and probably did more damage than good. A few weeks ago I used a fender roller and they came out MUCH better and I don't have to worry about rubbing any longer. I still haul stuff around in my car too, so I hear what you're saying about wanting to actually use the station wagon for it's inteded purpose. Hell, that's the reason I bought my wagon, to haul my gear around.
There are a lot of great wheels and tires out there and do your research and triple check all the number. I would honestly go with a 205/40 tire if you plan on having your friends and gear in the car a lot. Yes, they aren't as wide, but you won't need to worry about rubbing. Then again, it could just be my particular car and set up. Some cats run 215/40 tires and don't rub at all.