All appreciated, and I'm only trying to suggest something that might help.
You are right you dont want the sun in their faces with all high contrast and squinting that goes with it, which is why I usually aim to put the sun just off centre behind the group. The high vantage point of the camera, coupled with a good, (dust free) lens and a hood will usually sort out any flare and lack of contrast. If you get it right, the sun will kiss the backs of the heads giving a great rim light to the guests.
Its all about practise Steve, and I would say having only been doing weddings for 3 years, I syill have lots to learn.
The big group is always a difficult one, as you have to work fast to keep everyone interested, and its more about handling the people not just the camera. You didnt do bad in the end, but I think with time and practice you will learn you wont need 3 speedlights on such a beautiful day and you will get to find the light you need.
I didnt really dare shoot into the sunlight until I spent some time on Damien Lovegrove courses, and learned to trust my gear. He also taught me that the £70 filter I was using to protect my lens wasnt worth all the hunting for focus when facing the sun, and removing it greatly improved my confidence in the lenses.
Keep up the good work and like the rest of us, you will learn from your experiences.