Hi there, congratulations! Such an exciting time.
I agree with Niki Lea - comfort is so much more important that style for the first few weeks. I agree with the suggestion to avoid crewnecks, at least for the first bit, if you are planning to breast-feed. A few cardis and/or casual jackets will add some coverage (both for shape and nursing purposes; a large scarf would be good for this too) and structure when you have to head out.
And - to add some unsolicited but hopefully not too annoying extra advice - can I also suggest considering one or two pants with a forgiving waistband (both to accommodate post-baby shape and for comfort should you have a c-section - fold-down yoga pants or leggings are great for this and a nice change from your maternity pants!), and a few extra jammies too, as you may sweat a lot at night and need to change jammies more frequently than usual. And maybe a non-shape-related splurge like a pedi or a lovely new lipstick, just for happiness
Good luck and congratulations again!!!!!!!!!!!!!!!!!!!!!!