Wedding Dress Advice! Alterations...

hnk2c

Hello, I need some advice on customizing my wedding dress. I just purchased this dress (Ella 5468) 

and I want to make some alterations to the back of it to make it unique, fun, and interesting. I would love to have some sort of low or open back (maybe keyhole?), to remove the corset and put in a zipper, and to maybe add some sort of straps depending on the style of the back. 

My biggest concern is keeping the fit the same. I love how the corset keeps the dress fitted and tight, but I bet there are ways to change it and still have the fit. 

Any advice would be greatly appreciated!

I was thinking of these as ideas: 

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