Hi James,

You mention the Canon 50 f/1.4 L. Did you mean the 50 f/1.4 or the 50 f/1.2 L? I see you have the 50 f/1.8. That was my first prime lens. I upgraded to the 50 f/1.4 about two years ago. It is a much better lens, IMO. The nifty fifty is a great lens, but I didn't care for the AF and prefered the sharpness starting at ~f/2.8. The 50 f/1.4 has much better AF (still leaves something to be desired) and I like the center frame sharpness starting at ~f/2. It also has a little bit of pop to its photos that I like.

Regarding your actual questions. My first recommendation would be to try to go to the church and test out your current lens lineup to see how it works from different vantage points and what exposure settings you need, assuming the church is reasonably close to you.

If that can't happen, I actually think you have wide covered with the EFS 17-55 and the EFS 10-22. As a guest, I shot a wedding two years ago that looks somewhat similar to the church in your link. My 7D and EFS 15-85 did pretty well (a number of my photos have been used by the couple). My exposures were ~1/60, f/4-f/5.6 and ISO 800-1600. So I think f/2.8 may be enough, in which case, and considering your EFS 17-55, I would be tempted to buy or rent a 70-200 II. If not that, I would be tempted by the 80 f/1.8 or 80 f/1.2. Equivalent to 128 mm on the 7D, it would be great for closeups.

Regarding the 100 mm L macro. I enjoy that lens much more on FF than I did on my 7D. For macro work, it is still good on the 7D. For most other shots, it is long.

Hope that helps....Good luck,
Brant