I think that you can’t go wrong with any ic the options you mentioned and will look great in all of those options AND be appropriate. I also look great in sheaths, wrap dresses and lots of things.
@VeryHappy, LOVE that dress. I dressed up a little more than everyone else for my S’s rehearsal dinner and felt great about it. In our case, my DIL also dressed up, but the rest of the guests were in very casual wear, as we had indicated since the dinner was in a beer hall. I felt good in the dress I wore and that’s all that mattered. As for pictures, the only ones taken that night were of the cell phone variety!
VeryHappy is being modest. I like that dress, and really, I don’t think it’s attention grabbing. That would be lots of sequins and sparkles. This is just cheerful.
Thank you, @mathmom.
Nice dress, VH. I think you should wear it to the rehearsal dinner.
I agree with everyone else: wear it! The dress is fun, but ladylike as long as it isn’t very short, which I cannot imagine you would do. You will not look like mutton dressed as lamb, or as if you are setting up as Queen for a Day. 
Nowhere is it written that the mothers have to be dowdy.
I love the dress for rehearsal dinner.
Very pretty dress, VH. Not what I was expecting from your description. No reason at all you shouldn’t wear it.
Well, I guess it’s settled then! And if the bride or MOB don’t like it – tough.