Ok, so for our wedding my FH and I decided to ask our aunts to be ushers since they each know most of the people on their respective side. Because I was laid back with my bridal party and I knew that the ushers would be easily identified because they would be wearing corsages, I didn't see the big deal of being overly specific with what they wore.
They both asked if I wanted them to wear a specific color, so I told them blue (since our wedding colors are purple and blue). One of them came back with two navy blue options and the other with a white and multiple shades of blue dress. Eventhough they weren't the exact shade of blue that we incorporated into the wedding, I thought that both color options were good.
My dilemma is though that now I am starting to double think it, mostly because my FMIL is saying that we need them to coordinate with the wedding colors and being a different shade than the one we have for the wedding won't match or look good. Both of our aunts aren't exactly swimming in money and as a matter of fact, one of them is re-using a dress from a previous wedding and another is borrowing her dress from a friend. I would really hate to make them have to spend more money than they already are (they both live abroad and his aunt's young son is part of the bridal party) to buy new dresses just to satisfy my FMIL because she feels something as simple as this could make the wedding "look bad or cheap", eventhough my original goal was to have a laid-back type wedding.
As a note, my bridal party is wearing lillacy-purple dress, but they are all different styles, so not even the bridesmaids are an exact match.