Hey, I like the suit. Men's warehouse has made more money off of me than I care to admit. I agree though that it's not a "wedding" suit if you're going to be the guy standing up front next to the lady everyone is looking at. Those wedding photos are going to be around for a looooooong time.
My two cents: Dark suit, not black. Black is too stark. I know you said no navy or charcoal, but I think it's the right suit for what you're going to do. Pin stripes are ok, but don't get the big fat chalk lines. They make you look like a pimp. The suit you're wearing in the photo is edging toward that. I've recently become a big fan of the subtle plaids/window pane patterns. There are lots of other subtle patterns out there too. They're nice Then, dress it up on the cheap. Get a spread or a semi-spread collar and put on a good tie with a windsor knot instead of that four-in-hand knot in the picture. Wear a pocket square. Make sure your tie is about the same width as your lapels.
For shoes I'm all over some cap-toed lace-up oxfords. It's a wedding for goodness sake. Square toed and brown doesn't really tell me enough to say if that's a good suit idea or not. Especially if they're light with a wide square toe, they'll look dumb if you follow my advice on the dark suit. I know this because I recently spent all day looking at my coworkers thinking how dorky he looked for doing exactly that, while at the same time cringing because I had a pair of shoes that looked almost identical that I loved. I haven't worn them to work since.
Shirt: go with white or blue. Again I caution about the longevity of wedding photos. How many dudes that are in their 50s today are cringing at having to look at the photos of the blue ruffle tux they chose to wear in '79? All of them, that's how many. I love wearing colored shirts with suits, but I don't do it if I have something really formal to go to. Get something classic, get french cuffs, wear non-novelty cuff links. If you actually walk into men's warehouse to buy your suit, they'll lay out a bunch of different shirt and tie combos under the jacket to show you how they look. Buy the tie and the socks, don't buy the shirt. You can get that somewhere else because it will be about $80.
Final piece of advice (damn, I'm verbose for having not even had coffee yet...) If you know your measurements, look on ebay. I just picked up an amazing Brooks Brothers suit for $100. That's about 10% of what it cost when it walked out of the store.
