Joyce, first of all, the sandals are super fab! Great purchase.
Second, I love that first sheath on you -- so very pretty. And the fit and flare also looks lovely. Both are feminine and fresh options, very ladylike without being precious, and they show off your delicate bone structure to perfection.
I think you need a more cropped jacket. The lace moto can work (and is nice for the added dressy factor). But if you want a different jacket or a jean jacket to dress them down later, you need a shorter version.
Can you please remind me how tall you are and whether you are short waisted? I ask because at 5'4, I had GREAT luck finding a white jean jacket at Old Navy in the KIDS section. Very inexpensive and works great as an over-a-dress topper.
I wouldn't wear a jean jacket to the wedding or the grad, but it might be nice to have to dress down the dresses for other occasions this summer.
The proper length for a jacket with a dress varies depending on the wearer's height and proportions, the shape of the dress, the cut of the jacket, and the effect you are after. Angie has a few blog posts about this somewhere in the archives.
Denim jackets tend to be quite boxy and in any case the fabric is stiff. So cropped is better with a dress. You could wear a linen jacket to your high hip, I think.