Pre Wedding Portraits

I had a pre wedding meeting yesterday with a couple we are covering in a few weeks and I thought I might use some off camera flash, I've been reading a lot of strobist, if you haven't been it's worth a look for techniques and inspiration. Anyway as the sun had pretty much dipped over the horizon I wanted to do something with the sunset, but not have the couple as silhouettes, so in full manual I metered for the sky and got f5.6 at 1/160 sec (ISO100) I had a flash to the left through an umbrella and it was just a case of changing the flash power (I ended up at about 1/4 power with an old SB28, I know, a Nikon!) I could have darkened the sky by simply adjusting the shutter speed. I tweaked the shot in lightroom, I originally added a textured layer in photoshop but decided it made the photo look like it was on a backdrop so I binned it. I was going to do a mono conversion but decided it wasn't necessary