Yellow is a great color on the floor--it shows up really well.
Don't be worried about being too bright. The lights on a comp floor tend to wash everything out, and you will be seen from a distance, so it won't look too vibrant.
I would put some stones on it, or it will look unfinished. You don't need to go overboard, but perhaps line the neckline and sprinkle some on the bodice.
I like the fishing line hems, too, but they are out of style. If it's a subtle effect, you could keep it if you really wanted, but if there are distinct curlicues, I'd remove the wire.
Good luck on your comp! I'm sure you'll look beautiful! (What are your plans for hair and makeup?)