I replied to your post the other day, so coming back to say that the dress on the left is still the winner in my mind! It’s stunning and looks like it was made for you.
If you want a “train”, you could think about getting a cathedral veil that has lace on it. This would give you that extra oomph you’re looking for when walking down the aisle and in pictures (although honestly girl, you do NOT need it in that dress, you will be the star of the show), and then it’s easy to remove for the reception. The train really only shows up during the ceremony and pictures, it’s usually bustled the rest of the time so that you don’t trip over it.
You could also look at a detachable train to add to the dress. This can definitely have an impact on the silhouette, but they come in a few different styles.