Okay. 
I can’t help you out with shoes and wedding outfits, but there are a few tips and tricks knocking about to make lingerie shopping a bit easier.
As I alluded to above, knowing your measurements is really helpful. That way you can use the size guides, as well as any of the lingerie reviews with the reviewer’s measurements in too. There’s a good How-To in the Tester Guide. 
And if you consider the areas you want to emphasise, and the ones you maybe want to obscure a little, that can help narrow what styles you might like to try. Mrs Chimp is a fan of Baby Dolls and Bra Sets (particularly the longline ones) as she likes a bit of mummy tummy coverage - and if she’s feeling particularly fruity she likes a basque and stockings too. Here’s a lingerie style guide with a bit more info in.
I used to suggest finding a ‘body buddy’ in the reviews who has a similar size/taste to you so you could read what else they found that worked, but unfortunately the new review system doesn’t work like that now. Fingers-crossed they come up with a fix for it though. 
The return policy is really good, but it’s a faff to have to take a trip to the post office if you can avoid it. So anything that makes it easier has got to be a good thing.
(apologies, it’s a little rushed. I’m cooking dinner )