Would it be crazy to change the neckline? I mean, take it to the taylor and see what can be done, if he/she can open the neck a bit or something. I would go for a boat neck, V-neck might be a bit too much given the shortness of the skirt. I love how the difficult colors pair perfectly with your skin-tone -believe me, I look horrible in yellow- and it would be a pity that you wouldn't keep it.
In all honesty, I'd wear the dress just like that, no jeggings. I understand that you are in your 40s, but you have nice and toned legs. I think that 'modesty' is age-related partly because as we grow older, our bodies don't look as nice as they used to so we need to cover up, I don't think it has that much to do with 'sexiness'. As long as you feel comfortable showing your beautiful legs -which are more than fine-, I don't think it'd look indecent. Yesterday I saw one of my friends' mom, she's 58 and still wears skirts that hit quite above her knees. She's got incredible legs and the right to flaunt them!