Haha Sarah! You're making me laugh! I vote for #2 because they are super cute and they are comfortable (and I'm wearing them too). I like the bling on #3 but from experience they are not very comfortable and they might be too high for your dress. I don't think you'll hear the clank of the shells too much when you walk down the aisle for a few reasons a) your dress will muffle the sound you're not going to be walking in silence...they'll be some sort of music as you walk, right? c) nobody is going to be listening to your shoes, they'll hear the ocean over your shoes.
#1 is classic and pretty and would be nice too, but they don't quite have the beachy feel that #2 has.
I'm assuming the ebay shoes came okay and were in good shape? can't wait to hear what you decide!
By the way, did I mention you have great taste in shoes?