Can a wedding dress be too plain?

I've been searching all over the internet, looking at wedding dresses, because my Mom is going to be visiting from N.J. and we're going dress shopping! I wanted to figure out all of the parts of a wedding dress that I prefer like the neckline, silhouette, and materials. It looks like I'm leaning towards a more simple dress. Why do I feel like I'm going to regret picking out a pretty, but plain dress? Here's an example of what I'm liking...