I can't give too much advice on an outfit as I don't usually shop for quirky items- I am far too boring! However I thought I could offer some other advice on the wow-ness!
Hair, makeup and nail polish can make all the difference in the world. I can be wearing the worlds most boring plain black dress, but if I have my makeup done nicely and my hair blow dried it makes 100% of the difference
I rarely get my nails professionally done, I just buy a few shades from Boots/Superdrug usually that are gel nail polishes, and the gel top coat too and your nails can look professionally done
I also own a big round metal brush to try and professionally blow dry my own hair. Its quite time consuming it can take between 20-40 minutes but if I am going to a special occasion it is definitely worth it
For makeup, I usually watch a few Youtube videos on the look I am after (usually soft makeup look/glowing makeup etc) and use this as inspiration. If you searched middle aged woman for makeup something will definitely come up
Jewelry makes a huge difference too, a few rings, a nice watch and a nice pair of earrings can really make an outfit.
Sorry I couldn't offer much in terms of an actual outfit- but I could have the worlds nicest dress on and unless the rest of me is "done up" I don't feel wow.
I'm sure you will look beautiful whatever you wear!