The fancy dresses can be very expensive and if your daughter is still growing, it won't fit her for a long time. If you do decide on a fancier dress, look for a used dress sale. You will find competition dresses that have been worn only a few times for sale at a fraction of the original cost. It can be difficult when your child is in a simple dress and the other competitors are wearing fancy dresses. Remember, it's the quality of the skating that is most important and having fun at the competitions.
Simple lines work well on most body types.
When decorating, many designers think the more, the better. I actually disagree with that notion. I think that the skater should be wearing the dress, not the dress wearing the skater. Since your daughter prefers simple dresses for competition, you may want to just add decorative work around the neckline and the sleeve cuffs of the dress. It's interesting that one tends to see a lot less of that at higher level competitions.