Of course, you'll never go wrong with black! And obviously purple since it's the color of the dress..but make sure to not have the same color of purple! If you want to change it up you could definitely do a nice silver, not really shiny but maybe more glittery...or even a nice and light gold or nude shoe.
Also, if you're told to be comfy you should go with flats, ballet slippers would look nice and classy. Unless you're like me lol who always wants to wear heels then you could always take a pair of flats in your car or something...just an idea
It also depends on how you are going to accessorize... it would look nice if you had black shoes with a black clutch and black jewelry etc. You could even do another color like the ones aforementioned or like you said a coral and color up the outfit with a theme of spring-like colors..I wouldn't do a mint green unless the specific shoe looks nice..But don't go crazy with super vibrant and bright colors lol
I have a pair of redish-orange heels and I think the color would look nice..it doesn't let me post a link but just google Dany - Tomato Red Nubuck Jessica Simpson so you have an idea of the color.
In the end, it's up to you really and your style...just make sure to not go all multi-colored lol as long as there is some kind of theme with the accessorizing etc. The dress is very nice and I'm sure you'll pull of the look however you decide to wear it!
Hope this helps, if you have any other questions let me know! Have fun:)
Black ballet flats! They're pretty comfy when you put some inserts in :) black usually goes with anything so if you find some comfy black flats you can continue to wear them with any look! From casual,dressy or just going out with some friends. I have two pairs, ones leather with a braided band on the toes and the second is patent leather ( I think!) which I wear with anything. :) so just add some accessories and viola! You got it (:
You can never go wrong with black or nude. But you should maybe try a lighter purple (like lavander) or silver (just not the metallic shiny ones). Also if you want to look more playful try coral or red.
It really depends on your jewelery and bag, but any of these will probably work with silver jewelery.